Remember those dorky Bluetooth earpieces? The ones only MBA nerds wore? They were uncool until the AirPods came along.
The tail wags the dog. Wearing glasses may become inherently cool if all the cool people in your insta feeds are wearing them.
There is a UI difference between looking into a camera and talking to someone with headphones on.
There is a UI difference between looking into a camera and talking to someone with headphones on.