I don't see why Charging cables won't just start coming with an adapter that lets you plug in headphones. It's either stationary, so the extra bit doesn't reall

I don't see why Charging cables won't just start coming with an adapter that lets you plug in headphones. It's either stationary, so the extra bit doesn't really matter, or you're already carrying the cable + battery, and you probably don't care about the extra piece too much.