Waterproof?
Can anyone from Apple confirm that the iPhone 13 is waterproof? Or is it just resistant? Meaning, if I were to submerge my phone under water, is there a chance it will break and if it does, does it go under warranty?
Question marked as
No. No phone is waterproof.
If you intentionally submerge it you are abusing it and it will not be covered by warranty. The ad-men have a certain amount of artistic license.
Water damage
Water and other liquid damage to iPhone or iPod isn't covered by warranty - Apple Support