Yes, you're right, there are technical benefits too.
Still, I think the primary reason Apple felt comfortable dropping the headphone jack while contemporary Android phone vendors didn't, was that Apple could afford to lose customers who didn't want to upgrade to AirPods or other Bluetooth headphones. What they lost in direct sales they would regain in brand reputation. That was about market positioning, not about engineering.
By the way, I just looked up some specs and my unfashionable Samsung Galaxy A52s with a headphone jack also has an IP67 rating, and it is the same thickness as Samsung's current flagship model, Galaxy S23, which doesn't have a headphone jack. Both devices are only 0.6 mm (7%) thicker than Apple's current flagship iPhone 15. So while I'm sure adding a headphone port incurs some engineering cost, I feel like this cost isn't insurmountably high, and it's not true that you can't have IP67 and a headphone jack at the same time.
Still, I think the primary reason Apple felt comfortable dropping the headphone jack while contemporary Android phone vendors didn't, was that Apple could afford to lose customers who didn't want to upgrade to AirPods or other Bluetooth headphones. What they lost in direct sales they would regain in brand reputation. That was about market positioning, not about engineering.
By the way, I just looked up some specs and my unfashionable Samsung Galaxy A52s with a headphone jack also has an IP67 rating, and it is the same thickness as Samsung's current flagship model, Galaxy S23, which doesn't have a headphone jack. Both devices are only 0.6 mm (7%) thicker than Apple's current flagship iPhone 15. So while I'm sure adding a headphone port incurs some engineering cost, I feel like this cost isn't insurmountably high, and it's not true that you can't have IP67 and a headphone jack at the same time.