Over 85% of the headphones sold are wired and it's because they sound better and are more convenient. Bluetooth headphones have been around over 10 years, they are a niche business, they cater to joggers and gym rats.
The third parties that are making Lightning headphones are no-names that view Apple compatibility as a ticket to a business model. Another niche.
A headphone wire simply isn't inconvenient for those of us who don't run or go to the gym every day. They sit unused in a backpack for a month, when you need them they are there and don't need charging, and when in-use they weigh nothing and don't bother you as you sit on a train or in a plane. And those who care about audio quality would never seek a wireless option, they sound lousy, they are hissy, they have frequent dropouts.
Apple has been off the rails since the Beats acquisition, it's going to do down as the Edsel of the digital age. Apple Music, bust. Apple Connect, bust. Apple Music Radio, bust. Beats Headphones, downtrending. Next will be Apple Music HD where the files will be gigantic, they'll cost 2x more, and there will be some supposed "digital reality" sound experience, no different than quadraphonic LP's or 3D HDTV, just another rejected attempt to repurpose the same old content again and again, like I need to purchase Sargent Pepper a 15th time in my life.
BJ