This would great and worth consideration if helmets weren't disposable items. Obviously a crash will cause a write-off (and good luck convincing insurance your helmet was $2000). But helmets get stinky, they get dropped, they get exposed to UV. A five year replacement cycle is recommended by the Snell Foundation. [1] Okay, so $400/year; some folks will part with that. You'll cry real tears if you drop it hard enough to crack that carbon fiber shell.
Then there's fit. Some people have a Shoei head, some an Arai head (helmet brands). For $2000, that sucker better not cause hot spots on my noggin.
Replacement shields? Shields are consumables, IMO. And I want a dark one for sunny days, a light one for when I'm out after dark. I want a new one when the original gets scratched up.
I like the idea, but a cool HUD is just one thing to consider when buying a helmet, and not high on my personal list if I'm wearing the thing up to twelve hours a day.