I found a video of a hotel door lock installation. Hotel doors feel massive because they are built to resist fire which has been the #1 killer of guests, but pay attention to the first minute or so of the video and notice how much of the door is mortised out to make space for the lock. And no, the lock screws do not add strength back, they just secure the lock in place.
You may have seen me say here that a good shove is enough to crack a door. I speak from position of experience as once I was helping a maintenance engineer with a door that had a lock which simply collapsed leaving the guests locked inside. We were able to get the guests out via the connecting door to the next room, but we still had to deal with the dead lock. At one time, I was asked to give the door a good push from the outside… and I did. Nothing major, I did not take a couple of steps back or anything, I just laid my shoulder against the door and gave a big push.
I heard a “crack” and stepped back. The wood around the lock had failed and I had shoved the door is about 2 inches from the frame. I stopped in horror and figured my next paycheck was going to be light by a lot. Long story short, a new door was installed, insurance took care of the expense and I gain a new level of distrust for the sturdiness of hotel doors.
If I stay in a hotel, I will place the spare chair, my luggage and whatever else can be easily moved against the door when I go to sleep. I may not stop a dedicated attacker, but it will make noise and give me time to get my hands on something that will change the mind of an invader.
Now you know. Travel safe!