Door stopper for hotel room

Browsing around the internet I stumbled on this doorstop.
Quoting the product page:

Detects forced entry through doors / Loud 110dB+ alarm sounds when the
door is opened / Strong deterrence against intruders / Easy to install
/ Indoor use only. Alarm sounds loudly when there is an attempted
forced entry through a door – A great form of theft deterrence.

It sounds like something you are looking for.

_{Full disclosure:
I am not affiliated with the manufacturer or seller in any way. Just found this and it reminded me of this question.}

A door stop alarm is in fact a good precaution against unwanted intruders (in case that you are traveling, NOT for home) and I do not share the pessimism of the other answers because there are several good reasons for using it.

The intruder causes the alarm for a reason: He wants to intrude while you asleep. In sleep, you are helpless and immobile. A thief can easily steal something, a robber or worse can easily overpower you. Even if you wake up (“Hmm, whats going on ?”) you are disoriented, you need several seconds to clean your mind and understand the situation. Even then if you understand that someone is in your room, most people cannot act in full defense because they are under shock.
In fact, robbers use exactly a blitz attack on the victim because they know this.

It does not matter that the door stop cannot hold out for long, this is not the purpose of the device. It matters that really every second gives YOU an advantage and the INTRUDER a disadvantage.

Advantage for you: Every second wakes you more up. Your body is alerted and ready for fight/flight. You can easily see in the dark, the intruder not (in case the floor is lighted). The deafening sound masks what are you doing. And very important: You can move.
You can throw yourself against the door, barricade it, search your pepper spray or flee
through the window if necessary (ok, not on the 3rd floor).

Disadvantage for the intruder: He was prepared to follow his plan. The alarm and resistance will surprise him, give you precious seconds because he needs to adapt his plan
(In reality, thieves will almost always give up at that point and run). He cannot see you, he does not know what are you doing and where you are. Attention is raised, he takes the risk that every moment he will be witnessed or attacked.

There are really only two reasons for the intruder to continue after raising the alarm:
a) He/She knows that noone will be alerted (no persons or persons too far away) or that noone cares (fear, bad neighborhood, being a despised person, violent country) and
b) that they use violence to get what they want.

In the majority of cases it is not fulfilled because thievery/burglary is much more common than robbery/assault and therefore using the door stop is preferable. Even in the robbery case you have a possible option of escape through the window.
I agree that an armed robbery without escape possibility only leaves the option to give up your possessions as fast as possible. But this is really the rarest case.

A basic rubber “door stop” is probably a good idea to stop sudden rapid intrusion,
a properly sized prop with a non slip end under the door knob is said to work well,
and a chest of drawers against the door may slow people down.

BUT

attempts to stop serious violent and lawless invaders may cause more problems than they prevent.
Consider whether this is the case when taking precautions.
If so, you may not wish to visit at all or may need to enter the local “arms race”.
Some years ago a journalist attempted to hold a door shut against intruders in Afghanistan. – successfully enough that they shot him through the door.
He died :-(.
His fellow room-mates were robbed but, I understand, lived.
It’s possible that all may have been killed if he hadn’t resisted or that none would have been.

A friend of mine in Papua New Guinea was one of 3 men who were robbed at shotgun point by “Rascals”.
He was certain that he was going to be killed but none of them were physically harmed – he lost a watch and some money.
If he had locked himself in their vehicle the outcome may have been worse. Or, it may not.

ie decide in advance what course you wish to take in such situations.

I do not think you will turn up with a satisfactory solution with the term “door stop” since anything that I would call a doorstop (something that wedges between the lower edge of the door and the floor) is highly dependent on the floor type. On a carpet floor, certain materials might have a completely different effect than on tile/marble.

Further, even if there are chains installed, doors can be opened as you can see in this youtube video and also here. On top of that, there is a serious security flaw with a very widely distributed hotel lock.

When it comes to security, I would consider against whom/what you actually want to protect yourself and then act accordingly. Are you afraid your valuables are being stolen? Maybe the room safe is the best choice then. Or is someone after you personally? Try to figure out how to lower the risk of you being a target instead of trying to prevent the consequences of you being a target to happen.

Since on the downside, if someone is determined to get YOU as a specific target, there is little you can do. On the upside, there is probably a lot you can do if someone randomly picks you or your hotel room as a target to keep the damage low without trying to prevent them to enter your room, which is likely much more difficult.