I have explained, at length, why Apple removed the headphone jack. Money doesn't mean you can change the rules of physics. Either he removed the waterproofing or just messed up his barometer. One of the two.
Don't want to be pedantic, but iPhone is water resistant - not waterproof. And do you mean to say that no smartphones exist in the market that have a headphone jack, and still offer similar or better water resistance as iPhone 7 (and now 8 and X)?