It’s actually not as large and bulky as you might think. These ideas aren’t mutually exclusive is the thing. My old work phone was a Samsung XCover. They have replaceable batteries and are waterproof.

They’re a little bulkier than my 16 Pro, but not by that much, and the bulk isn’t really for waterproofing reasons alone.

Seal the phone and leave the battery compartment just weather proof. You’ll still be able to drop the phone in the toilet or whatever and the phone will be basically identical except with a slide off back. We’ve done it before, it’s not impossible.

Again, the idea that having devices be user serviceable leads to them needing to be designed to not be dust or waterproof is just a lie sold to us by the manufacturers. They could make our devices user serviceable, but they choose not to. Every time they’ve been coaxed into even a little bit of consumer friendliness, they oblige in the most malicious ways they can.

What I’m saying is, you don’t need to play the Devil’s Advocate. His position isn’t based on reality.

The majority of people don't need phones that can survive underwater. Most get exposed to a bit of rain occasionally and that's it. So even if it was impossible for both to exist (it isn't), we don't need it anyway. People are sold "IP68" or whatever because it allows manufacturers to make their phones harder to repair, that's the only reason.

Take a look at the latest gopros. They work underwater, are tiny, and have replaceable batteries. All you need is a watertight seal, and they've gotten those down in size by quite a lot.

When I screw the lid onto my coffee cup, it becomes waterproof. Nothing gets in and the coffee doesn't come out. Waterproofing doesn't require an adhesive.

There are plenty of phones that were designed, manufactured and sold with these two features.

Not all of them use the "case around a camera" approach (although a lot do, admittedly). The Olympus Tough series of cameras don't, for example. And really, phones would have pretty simple seams around the battery.