Which of course is not a problem for the thousand, or even millions of people who only have an iPhone...at least for personal music consumption.
That's not true though. I might be one of those "millions" and just took a trip and took along my 3.5mm headphones. Take that trip with me again AFTER you adopt this "the future"...
On the plane, they're showing the big game or a movie or TV show we want to watch & hear. What jack will the plane most likely have for audio even 5 or 10 years from now? I plugged right in. Yes, you could buy those cheap, almost throwaway headphones from the flight attendant for $5 or $10 but really? Do you want to buy those? Or just do without?
At the meeting, the corporation wanted us to view the latest demos. Plug in. My headphones plugged right in. There weren't enough spares laying around. Are you going to miss the demo because you can't plug in? Are they wrong for NOT being all Apple and all in on Apple proprietary?
Email: you just must see this on your Mac! Can you just plug in? No. No Macs have Lightning ports. Better dig up that adapter. Else, you just won't be watching "this". Or lay out the cash to buy new Macs that presumably will allocate some precious port space to Lightning. Why? So we can use that much bigger port to use headphones with our future Macs. Personally, I'd rather have another port that can do a lot of other things, but, of course, Apple always knows best.
A spot of togetherness. Let's share a movie. Your iPhone screen is too small, so lets use your Mac screen. Oh you can't plug in because you lost your adapter? And your honey can't plug into your iPhone because their headphones terminate in 3.5mm or USB3C. Maybe you two should break up? Who wants a honey that doesn't comply with Apple proprietary anyway? What did you ever see in them?
Ubiquity without a pile of proprietary licensing fees is a thing to treasure, especially when there is really nothing wrong with it (our ears can only hear analog). Even if one can live most of their time inside the most walled of walled gardens, life will inevitably roll out situations where opportunities to just plug in present themselves. Miss those opportunities because some corporation wants to push proprietary? Carry adapters always with you to be ready for such opportunities wherever they may pop up? Or wish the corporation would focus their big, BIG brains in OTHER areas begging for "innovation" that doesn't come with a string of licensing fee profits but seemingly next to nothing to gain for the buyer of that product?