The headphone connector is already pressed close to breaking point in my pocket, I can't have something even bigger sticking out of the phone in a tight pocket.
There are plenty of waterproof phones with headphone jacks.
With that in mind removing the 3.5 jack does not make the phone sleeker you need to see the adapter as a part of the iPhone as the phone is mostly useless without it.
It's the exact same size as the 6s.
It may be a smart move in the end, but it's not obviously so at this point.
Yes, another proprietary connector no better at it's task than the equivalent industry standard connector.
I lose headphones like crazy, and I'm not an audiophile, so my average spend on headphones is under $20
There are other similar models around the same price. You don't have to spend $100+ to get similar audio quality to $20 headphones that happen to have Bluetooth as well. Bluetooth chips are stupid cheap these days, pairing that with a small battery really doesn't add much to the cost of normal cheap headphone equipment and you'll find plenty of pairs <$40.