their AR stuff doesn't take off, because they always try to sneak in some registration or subscription to their shady services. when people need an FB account to use a device that can constantly record everything they look at and what they maybe want to use to do NSFW things, they don't want FB to have that info. the only people who wouldn't care are children and it's too expensive and boring for a childrens toy.
Everytime I try and think about the cool stuff I want from the the apple headgoggles I find that these glasses type devices would be perfect for my use. Then I find out these glasses are packed full of proprietary apps and subscriptions and I give up. Also they're to expensive :(