What is the biblical basis for all people meeting God when they die?

What is the biblical basis for all people meeting God when they die?
There are multiple passages that support this.

• Over and over again, Christ is pictured as our high priest, our advocate [defense attorney] and the one who intercedes for us to God the Father. Throughout scripture, in fact over 60 times in the Old and New Testament - God is named as the judge. Because God is totally pure and perfect, he cannot just overlook sin.

Psalm 75:7 But God is the Judge; He puts down one and exalts another.

Psalm 50:6 And the heavens declare His righteousness, For God Himself is judge. Selah.

2 Timothy 4:8 in the future there is laid up for me the crown of righteousness, which the Lord, the righteous Judge, will award to me on that day; and not only to me, but also to all who have loved His appearing.

Hebrews 12:23 to the general assembly and church of the firstborn who are enrolled in heaven, and to God, the Judge of all, and to the spirits of the righteous made perfect,

Source: https://bible.knowing-jesus.com/topics/God,-As-Judge

First we need to understand the concept of the great white throne judgement, which is also referred to as the Bema seat judgment. Bema seat was an elevated box for judges in the AncientOlympic games, and it also is a Hebrew word which means the elevated stand or podium in synagogues, from where the Torah is read. This phrase Bema seat is another term for the Great white throne Judgement.

Great White Throne Judgment From Simple English Wikipedia

"In Christianity, the Great White Throne Judgment is the time when the dead people that did not live during the 1,000 years that Satan was inside the bottomless pit come back to life and are judged by God according to their works using the 66 books of the Bible." Revelation 20:11-15

God the father is the Judge, and scripture says that for Christians - Christ is our "advocate"- our defense attorney - who intercedes for us to the Father.
In several languages, this Greek word advokat, is literally the same word used for defense attorney - Russian, Polish, Ukrainian and some other languages.

It is through the basis of Christ's substitionary atonement on the cross that we are justified - declared righteous by Christ. God looks at us as justified - Just-as-if-I'd never sinned [declared righteous] through the blood of his son - who was the Perfect spotless Passover lamb. Hebrews 9:26-28. This passage explicitly states that all mankind die once [refuting reincarnation] and that everyone will be judged. …26 Otherwise, Christ would have had to suffer repeatedly since the foundation of the world. But now He has appeared once for all at the end of the ages to do away with sin by the sacrifice of Himself. 27 Just as man is appointed to die once, and after that to face judgment, 28 so also Christ was offered once to bear the sins of many; and He will appear a second time, not to bear sin, but to bring salvation to those who eagerly await Him.…

Now, keep in mind the point of Christ, who is our advocate - who speaks in our defense to God, the righteous judge.

We see parables of this great final judgment in multiple parables of God separating the wheat from the tares, and also God separating the sheep [true followers of Christ] from goats - the impostors. Those who claim they know Christ but their actions or fruit proves they really do not.

Tares, especially in the early stages of growth, resemble wheat. Likewise, a false believer may resemble a true believer. In Matthew 7:22, Jesus warned that many profess faith but do not know Him. Thus, each person should examine his own relationship with Christ (2 Corinthians 13:5). First John is an excellent test of salvation. Jesus Christ will one day establish true righteousness. After He raptures the true church out of this world, God will pour out His righteous wrath on the world. During that tribulation, He will draw others to saving faith in Jesus Christ. At the end of the tribulation, all unbelievers will be judged for their sin and unbelief; then, they will be removed from God’s presence. True followers of Christ will reign with Him. What a glorious hope for the “wheat”! https://www.gotquestions.org/parable-wheat-tares.html

There are basically two kinds of people who are alive on earth, the living and the dead.

The living are believers in what God said about Christ Jesus. They have the deposit of the Spirit. They have been born again. For those people, to die is to leave the body and be present with Christ.

We are confident, I [Paul] say, and willing rather to be absent from the body, and to be present with the Lord. 2 Cor 5:8

For to me [Paul] to live is Christ, and to die is gain. Phl 2:1

And if I [Jesus] go and prepare a place for you, I will come again, and receive you unto myself; that where I am, there ye may be also. Jhn 14:3

The dead are people who have not heard of Christ who have not been born again. For these people, to die is to await the great white throne judgment of God where they appear.

And I saw the dead, small and great, stand before God; and the books were opened: and another book was opened, which is the book of life: and the dead were judged out of those things which were written in the books, according to their works. And the sea gave up the dead which were in it; and death and hell delivered up the dead which were in them: and they were judged every man according to their works. Rev 20:12-13

So, it is true that after a person dies they will meet God.

PS. The billboard was trying to convince the dead on earth to be born again because they were taught that once you are dead you do not have a second chance to believe what God says. The bible, however, says this about the great white throne judgment.

The books are opened and the book of life is opened. The dead are judged by their works in the books. All will fail because works are as filthy rags before God.

Then what happens? Death and hell are cast into the lake of fire which is the second death. And the dead who were present?

And whosoever was not found written in the book of life was cast into the lake of fire. Rev 20:15

Can they not as we have done here say I'm a sinner, my works born of my pride mean zero, I repent, I believe you God?

Revelation, chapter 21, verses 3 and 4 (KJV):

3. And I heard a great voice out of heaven saying, Behold, the tabernacle of God is with men, and he will dwell with them, and they shall be his people, and God himself shall be with them, and be their God.

4. And God shall wipe away all tears from their eyes; and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away.

i.e., every saved person will meet God in person (at least once) in the Heaven.

Revelation 1:7 New International Version (NIV)

“Look, he is coming with the clouds,” and “every eye will see him, even those who pierced him”; and all peoples on earth “will mourn because of him.” So shall it be! Amen.

This verse in Revelation does not prove that everyone throughout history will see God, but that everyone who is alive when Jesus returns will see Jesus, who is God the Son. The next verse is clearer:

Revelation 20:12 (KJV) And I saw the dead, small and great, stand before God; and the books were opened: and another book was opened, which is the book of life: and the dead were judged out of those things which were written in the books, according to their works.

Of course, it is good to hear it from the Lord himself:

Matthew 25:31-46 New International Version (NIV) The Sheep and the Goats 31 “When the Son of Man comes in his glory, and all the angels with him, he will sit on his glorious throne. 32 All the nations will be gathered before him, and he will separate the people one from another as a shepherd separates the sheep from the goats. 33 He will put the sheep on his right and the goats on his left.

34 “Then the King will say to those on his right, ‘Come, you who are blessed by my Father; take your inheritance, the kingdom prepared for you since the creation of the world. 35 For I was hungry and you gave me something to eat, I was thirsty and you gave me something to drink, I was a stranger and you invited me in, 36 I needed clothes and you clothed me, I was sick and you looked after me, I was in prison and you came to visit me.’

37 “Then the righteous will answer him, ‘Lord, when did we see you hungry and feed you, or thirsty and give you something to drink? 38 When did we see you a stranger and invite you in, or needing clothes and clothe you? 39 When did we see you sick or in prison and go to visit you?’

40 “The King will reply, ‘Truly I tell you, whatever you did for one of the least of these brothers and sisters of mine, you did for me.’

41 “Then he will say to those on his left, ‘Depart from me, you who are cursed, into the eternal fire prepared for the devil and his angels. 42 For I was hungry and you gave me nothing to eat, I was thirsty and you gave me nothing to drink, 43 I was a stranger and you did not invite me in, I needed clothes and you did not clothe me, I was sick and in prison and you did not look after me.’

44 “They also will answer, ‘Lord, when did we see you hungry or thirsty or a stranger or needing clothes or sick or in prison, and did not help you?’

45 “He will reply, ‘Truly I tell you, whatever you did not do for one of the least of these, you did not do for me.’

46 “Then they will go away to eternal punishment, but the righteous to eternal life.”

The short answer (from the Bible) is that after a person dies, they await the resurrection when they will face judgment. Nobody is excused.

Just as people are destined to die once, and after that to face judgment, so Christ was sacrificed once to take away the sins of many; and he will appear a second time, not to bear sin, but to bring salvation to those who are waiting for him. (Hebrews 9:27–28)

There are two resurrections, of the righteous and the unrighteous. That covers everybody. We are judged on what we did while we were alive:

And I saw the dead, the great and the small, standing before the throne, and books were opened. Another book was opened, which is the book of life. The dead were judged according to what they had done as recorded in the books. (Revelation 20:12)

The writer of the book of Ecclesiastes summed up the meaning of life this way:

For God will bring every deed into judgment, including every hidden thing, whether it is good or evil. (Ecclesiastes 12:14)

There is no biblical basis for thinking Saint Peter is standing at the gates of heaven to either allow or deny access. It's a charming thought, but not quite right!