You first video is a guy checking one single screen protector on an uneven rubber mat dropping a ball on it and not dropping the ball in the same exact place on the screen protector as the first two. The next two videos have some morons hitting a couple phones with hammers, and in the last video, aside from much of what linus does not being all that well thought out, he never does an impact test.

The three videos you found are very cherry picked and also poorly done, among dozens of others proving the coatings make no difference whatsoever in break resistance.

Also, aside from all the videos showing they don’t make your screen stronger, use your danged head. The digitizer (top) layer of your phone screen is around 0.6mm thick. Do you seriously think that a 0.005mm layer of anything at all is going to make your screen stronger? Not possible in the least. And if it were possible, dozens of companies have been making making that junk for the past decade. If it did anything, don’t you think Corning would have already been using it on their gorilla glass already? Use your head, man. All that junk can do is make your screen temporarily feel a bit smoother and make it oliophobic again for a few weeks. Putting it on under a screen protector would do nothing at all except make the screen protector not stick as well.