tl;dr apple won't do that because it's special

Shame on apple

One year ago I brought my PinePhone with replaceable battery into the sea and it's still working!

I could accept an adjustment where manufacturers only need to provide an option in the current generation, I.E. they can sell iPhone 16s that don't have a replaceable battery, as long as they sell an equivalent version that does. The argument for waterproofing seems fair to me, so the best approach in my mind would be to give that choice to consumers.