The headphone jack did take up a considerable amount of space and made waterproofing quite a bit harder. It't not like it was not a well-considered tradeoff. Companies don't work based on spite, but based on profit.
The existence of waterproof Samsung phones of the same thickness seems to disprove this line for me; it’s not a coincidence that AirPods were released at the same time. Removing the headphone jack and was at least in part about the upsell to wireless headphones apple also makes.
I concur. If anything, TRRS jacks should be easier to waterproof compared to other holes.