If Jesus was God (the famous John 1:1), why was He exalted to a higher position?

Philippians 2:9 indicates that Jesus was rewarded for the great sacrifice of humbling himself even to death on a cross. If he were merely exalted back to the place that he held before, what is the reward in that?

He was also given the reward of a name that is above all names. It is not the name of Jesus, Yeshua, Yehoshua or any similar earthly name. He already had that name before his death. It is a new name referred to in Rev. 19:12.

His eyes are a flame of fire, and on His head are many diadems; and He has a name written on Him which no one knows except Himself.

As is the case in so much about the nature of God, we are not given much detail about all that Christ’s exaltation entailed. Daniel 7 sheds a little additional light.

13“I kept looking in the night visions, And behold, with the clouds of heaven One like a Son of Man was coming, And He came up to the Ancient of Days And was presented before Him. 14“And to Him was given dominion, Glory and a kingdom, That all the peoples, nations and men of every language Might serve Him. His dominion is an everlasting dominion Which will not pass away; And His kingdom is one Which will not be destroyed. NASB

Jesus was God (John 1:1, "the Word was God") in the sense of agency (authorized representative), similar to how Moses was made God (Exodus 7:1, ""See, I have made you God to Pharaoh," but note that the 'as' or 'like' often found in the translations is a gloss added by translators) but more so (note the comparison at John 1:17 between Jesus and Moses, Jesus > Moses).

Jesus himself says at John 17:3 that the Father is the only true God.

Jesus also says at John 8:4 that He is a man who has heard things from God, which summarizes his role as the image (Colossians 1:15, "The Son is the image of the invisible God") or 'Word' (John 1:1, Revelation 19:13, "His name is The Word of God") of God.

But, Jesus - a man who is God in the sense of agency - is then exalted to the right hand of God (= the Father) after 'passing the test' of a faultless, fully human life that was ontologically open the possibility of sin, where He now reigns with all authority granted to him by God.

Easy-peasy, lemon-squeezy.

Jesus was exalted [...] (as if he wasn't in that position)

He wasn't; he descended down to earth (previous two verses), hence the need for an ascension, which is what exaltation means; see also John 17:24.

I was a Trinitarian

Apparently a Protestant or Evangelical Trinitarian; when doing the sign of the cross, moving the right hand from the forehead to the chest or abdomen signifies Christ's descent from heaven to earth, and its move to the right shoulder, His ascent to the Father's right hand side (Matthew 26:64, Mark 14:62, Luke 22:69, Acts 7:56, Hebrews 1:3, 8:1; 1 Peter 3:22).

If He was/is God, why after [the] resurrection He was [...] also exalted?

This is a dead giveaway, insofar both seem to befit His humanity; otherwise, in light of divine immortality, one could also ask:

If Jesus was God (the famous John1:1), why was He exalted to higher position resurrected, as if he wasn't in that position already alive to begin with?

Jesus was exalted precisely because he had been humbled during His incarnation, a process that the passage in Phil 2:5-11 calls the "kenosis", "became nothing", or "emptied Himself". Here is the passage in question:

5 Let this mind be in you which was also in Christ Jesus:

6 Who, existing in the form of God, did not consider equality with God something to be grasped,

7 but emptied [ἐκένωσεν] Himself, taking the form of a servant, being made in human likeness.

8 And being found in appearance as a man, He humbled Himself and became obedient to death— even death on a cross.

9 Therefore God exalted Him to the highest place and gave Him the name above all names, 10 that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, 11 and every tongue confess that Jesus Christ is Lord, to the glory of God the Father.

This passage sets out several facts:

1. Jesus was equal with God before the incarnation/kenosis
2. Jesus voluntarily became human (was "incarnated") and was humbled
3. Jesus voluntarily died as a human
4. Jesus, following the resurrection, was exalted, that is, his previous status in heaven was restored

This answered Jesus' prayer in John 17:5 -

And now, Father, glorify Me in Your presence with the glory I had with You before the world existed.

It is very significant that Jesus' exaltation described in Phil 2:9-11 is almost a direct quote (of the LXX text) of a prophecy in Isa 45:23 about what would happen to Jehovah/YHWH which effectively means that Paul, in Phil 2:9-11, is describing Jesus as Jehovah.

John chapter 1, opening verses, speaks of the one who was with God in the beginning, and who was God, and who made everything that was made. It then shows that this "Word became flesh and dwelt among us, and we beheld his glory, that of the only-begotten of the Father, full of grace and truth" (vs. 14).

As God the Father has no beginning, one who was with him and who was God could not have had any beginning either. Verse 3 confirms that without this one, nothing that was made was made. Logically, then, this one could not have been made himself. That is why he is called "God" by John, both here and at the end of his account - "My Lord and my God" - (20:28).

Philippians 2:9 (which you allude to but don't cite) is understood by those who have the Word as a creature (hence lower than God right from the start; not God) as becoming the man, Jesus, who could be exalted back to a certain level of glory after his resurrection. No problem, they think, except that such an interpretation utterly depends on the Word having a starting point in time, being created by God. They have John 1:1 say the Word was 'a god'.

But those who take John 1:1-14 as showing the uncreated status of the Word, see a far greater degree of abas*m*nt in that lowering. Then, at his resurrection, the Father exalted him from that abased position. This means that both groups agree on the sequence of events: initially exalted, abased, then exalted. The disagreement is regarding degree of initial exaltation, degree of abas*m*nt and degree of exaltation.

Those who believe the Word was God see God, in Christ, so identifying with humanity that they understand what doubting Thomas said (and felt) in John 20:28, whereas those who think it wasn't God in Christ just don't get it. Philippians 2:9 is couched in words of exhortation for Christians to have that same humility of mind. Further, it says that although he was in the form of God, he did not grasp on to that; He agreed to be made in the likeness of men and to suffer humiliating death, knowing the Father would exalt him.

The Father, Son, and Holy Spirit determined this plan of redemption before anything was created, which is why the Bible speaks of Christ as "the Lamb of God, slain from the foundation of the world" (Revelation 13:8). It was decreed and as good as done, for the Word of God is inviolable. That plan included exaltation of the one who abased himself, which is why it happened.

If Jesus was God (The Famous John1:1). Why was He exalted to higher position?

Paul answered this in (NIV) Philippians 2:

5 In your relationships with one another, have the same mindset as Christ Jesus:
6Who, being in very nature God, did not consider equality with God something to be used to his own advantage; 7rather, he made himself nothing by taking the very nature of a servant, being made in human likeness.

Jesus took on human nature.

8And being found in appearance as a man, he humbled himself by becoming obedient to death—even death on a cross! 9Therefore God exalted him to the highest place and gave him the name that is above every name

Jesus demonstrated the eternal principle in Matthew 23:

12 For those who exalt themselves will be humbled, and those who humble themselves will be exalted.

According to the context of Philippians 2:6 (specifically) the Son always was God. At Philippians vs 8 He was found in appearance as a man etc.

"Therefore" or as a result of the above God highly exalted Him etc. So, as a result of this obedience to the plan of the Father, the Son possessed something He did not have before His incarnation.

What did Jesus have after His crucifixion, resurrection, and ascension that He did not have before all this transpired? What did He take back to heaven that He did not have previously? His humanity! He always was the Son of God, but was not human until His incarnation.

So in conclusion Jesus Christ went from one form of being God, and took on another form of that of a bond-servant/man. He emptied Himself of the expression of deity, not the possession of deity. When He became flesh His deity was veiled or concealed. Hebrews 10:19-20.