The argument that you can’t have water proof replaceable batteries is silly, and it’s very obviously false, lots of gadgets do that.
Some make similar claims with mini jack, but that too is absolutely possible, for instance Sony has/had that.
It’s the same principle as waterproofing an USB/charging conecter, and AFAIK ALL phones with IP68 rating have USB/Charging ports.
Unfortunately if your IP68 phone has a glass back, that can easily crack, and that will compromise the IP68 feature.
In that way, my IP68 phone was only intact for 4 months. 😱
Maybe try to write why you are posting this? What is the significance of it?