How else can you resell headphones, again?
The only good thing that's being added is digital out. No more expensive docks...
However, muting and volume on the cable, any monkey can design that. I'm not even talking about passive volume, either. Plus you don't change the jack what-so-ever. You simply add a digital circuit that rides on the same line but doesn't go to the drivers, and then one extra rung on the 1/8 plug. My headphones that came with my HTC One M8 already has this extra rung, and a mute button. If you want digital you just use a different cable and select digital out on the same wires, without the digital bypass to analog circuit/add a connector midline on the volume control piece. And the phone can even not send any digital signal if it senses the wrong load for the digital, if you want to use traditional headphones.
It's not rocket science. How do you think DSL works while we talk on the phone? It's ancient technology.
What isn't ancient, is Apple proving they can up their asshole game to put is back into an archaic fart zone of non-universal equipment.