AR and HUD are two completely different things. AR is way more technically challenging but the payoff IF you pull it off is not even comparable to HUDs like go

AR and HUD are two completely different things. AR is way more technically challenging but the payoff IF you pull it off is not even comparable to HUDs like google glass and the examples you mentioned. AR actually "augments" your reality, for example it makes you believe some "thing" that's not actually there IS at that spot. HUD is just information display and it doesn't have to fix whatever it's displaying at a certain point.