Actually I think the real underlying motivator for ditching the headphone jack is just to fully usher people into a proper world of "wireless-ness". Hanging on to headphone jacks is like hanging on to a landline. It's just outdated and unnecessary. The only examples you guys provide for wired headphones are just a bunch of "what if" scenarios. You talk about how you might lose your headphones, how your headphones might die, how you might notice some loss of quality, how you might need to buy a $2 pair of headphones from the airport because you left your at home, etc etc etc. You just want it as a backup plan. Well we're past that now. We're no longer catering to the lowest common denominator. Bluetooth headphones work just as well as wired ones, are not difficult to setup, are more convenient to wear, and condition people into accepting a wireless culture so that they wont be so timid about other products coming down the line.
This is no different than when ultrabooks ditched the cd-rom drive and everyone lost their shit because "OMG but i have so many linux distros burned, I need those!". No you dont.
I don't think you really have a clue about what you're talking about. This is absolutely nothing in common to "keeping a landline". Headphone jacks are not outdated by any means. If they were actually outdated they would have been gone a long time ago. Headphone jacks are effectively ubiquitous. I can use the headphone jack on my PC, on my phone, on another person's phone (unless their phone unfortunately grew "courage") and with a hell of a lot of other devices. I don't have to worry about charging them. I don't have to worry about whether bluetooth is going to work today or not. I don't have to worry about pairing them, just plug them in and they work. I don't have to worry about sound quality because the sound quality is the same unless there's an issue with the device plugged into them. I don't have to worry about interference from other bluetooth or wireless devices. Even if something happens to my headphones I have spares already. It's not going to cost me $40, $50, $150 to replace them when the batteries die because they don't have batteries. I've had my current set of headphones for at least 10 years and am perfectly happy to continue using them; are you every going to be able to say that about bluetooth headphones?
Guess what, I'm past bluetooth already. That ship sailed long ago. I've had more issues than I care to remember with bluetooth over the years. I've lost count of the number of people I've heard bitching about their bluetooth device simply not working or pairing because of no known reason at all. The incompatibilities and issues between different bluetooth versions is legendary. The battery on my phone drains fast enough as it is, I sure as hell don't need the additional bluetooth drain on the device. Using headphones doesn't even cause a noticeable difference in battery drain.
And don't even get me started on the shit that is the dongle. Been there, done that. I'm wondering if you've even been using cell phones for all that long. Manufacturers started with the damn dongle instead of the headphone jack when they first started putting audio playback capabilities into phones. I remember and experienced that era. The dongles were shit. It was an extra item you had to keep track of. The damn things loved to fall apart for no reason. You couldn't charge your phone and listen on headphones at the same time. You know what fixed all that? Manufacturers finally wised the fuck up and put headphone jacks on phones and all these very issues went away.
Face it, there's no advantage to getting rid of the headphone jack for anyone but the manufacturers. People don't want even thinner phones and that's the only real "reason" manufacturers give for trying to get rid of the jack. They simply don't want to tell you the real reason is to sell more accessories.