LOL! I don't think any device will ever be THAT waterproof. It's easier, safer, and more effective to just get a UV sterilizer and toss it in there for 10 minutes. There's a device called Homesoap that will do even 14" MacBooks. You can also use it to sterilize your keys, credit cards, etc..I understand your concern, but I have been using Lysol disinfectant wipes #ad on all my devices -- Mac, iPhone, iPad -- for over a decade. There has never been any damage or discoloration caused by this. Just plain sterile goodness.
But it would be even more convenient if I can just throw my phone in the dishwasher or the laundry. 🤔