I know the XS Max is not meant to be water proof, but 30mins 2m depth IP68 gotta be worth something ?, nah
In the keynote they showed some guy diving down to pickup phone from pool, they said no worries it will be fine
So on holiday I had been snorkeling around with a £10 soft waterproof case no issue.... worked great. My lad was snorkeling in pool and my case was in hotel room so I thought, what the heck, lets film him and just be careful. Phone took some splashes and accidental submersion, screen started flickering, went green, then powered off. After leaving to dry with SIM tray out for two days it would power up but only for a couple of mins. Face ID stopped working as Truedepth camera borked, all cameras misted.
Anyways, don't assume you can submerge phone... I guess there is variability in manufacture
I took to Apple and confessed, and on opening it was completely full of moisture / corrosion and was a write off. Apple Care replaced for me, but not after paying the £80 excess....