I wonder if he can explain how the move to glass backs helped in durability?
Apple does not have to make devices harder to repair to achieve optimum durability.
Unfortunately, in some cases the point is basically moot because a repair can be so expensive that a user is 'encouraged' into getting a new device (or AppleCare of course).
Actually designing for repair would be a better option and is what that EU is edging towards. Apple has seemingly already made some minor concessions on that front. Maybe more to come?
I have long argued against waterproofing with seals if the waterproofing isn't covered by the warranty.
All the major manufacturers perform similar testing anyway and those making 'rugged' phones obviously do more.
The YouTubers do serve a purpose when it comes to comparing devices out in the real world. No matter the absurdity of some tests. Internal testing has to be conducted of course and there are very likely legal requirements on minimum levels but internal testing is inherently a non-public affair so no amount of screen scratch resistance marketing claims will ever be a substitute for a guy on YouTube trying to scratch a screen to death.