I certainly agree regarding the iPhone 7 Audio IC issue, Apple has consistently denied any design flaw on their part.
However, regarding you testing the water resistance, I disagree. Take a look at the specs for the iPhone XS Max (https://www.apple.com/ca/iphone-xs/specs/):
'''Splash-, Water- and Dust-Resistant^^3^^'''
Rated IP68 (maximum depth of 2 metres up to 30 minutes) under IEC standard 60529
Notice the little “3” in superscript. Here is what the fine print says (emphasis mine):
* iPhone XS and iPhone XS Max are '''''splash-, water- and dust-resistant, and were tested under controlled laboratory conditions''''' with a rating of IP68 under IEC standard 60529 (maximum depth of 2 metres up to 30 minutes). '''''Splash, water and dust resistance are not permanent conditions and resistance might decrease as a result of normal wear.''' ''Do not attempt to charge a wet iPhone; refer to the user guide for cleaning and drying instructions. '''''Liquid damage not covered under warranty.'''''
Apple is doing it’s darnedest to wash it‘s hands of any issues. For one, only ‘controlled-laboratory conditions’ (hand picked devices, perfect conditions…), secondly, they’re already distancing themselves from how long water resistance will last and lastly, they won’t even cover water damage under warranty. It’s pretty obvious that Apple does not have a high level of faith in the water resistance for any individual device. Anyone who willingly tries to test if a phone is actually water resistant should be prepared for a complete loss of functionality.
That doesn’t mean you don’t have grounds for a lawsuit but you probably could have saved yourself a lot of trouble. An iPhone remains a “computer in your pocket”, it is immensely complex and it’s quite frankly, when you look at the level of technology, it’s borderline miraculous that we even have this level of technology accessible to us in the first place. There are lots of reasons to be unhappy with Apple…but they are pushing the bleeding edge of technology on every new iPhone iteration. I fix heavily damaged devices every day and at times I am shocked at what people willingly subject their phones and tablet to.
Anyway, this isn’t really about you in particular, hopefully this will also serve as a context for others when they wonder if their phone can really survive exposure to water. The answer is “probably not”.