Anyone who hand-registered "decent" AR, VR or Holo names and thinks its a 2-3 year wait before the name mature to start seeing nice sales is a long way off. If you are hand-registering names in these tech niches, you really have to get in at least 5/6+ years before, sometimes even longer, to get the names really worth regging. The popularity of the niche also decides how long before you should have started regging names.
If you come into a tech 2-3 before it booms, you either have to register average names that will struggle to sell to end-users, or you have spend high xxx to low, or even mid x,xxx per name to get names that will sell to end-users (not domainers), and I mean regular sales to end-users, not 1 or 2 sales.
As
@BostonDomainer said above and I have said it many times on other threads, it doesn't matter how much we pump up the thread on here and various other platforms like Facebook, LinkedIn, Twitter etc..if the tech is not going to make it mainstream, its just not meant to be and no amount of marketing by domainers or bloggers like Robert Scoble will have any impact whatsoever.
We have just have to be smart and try and spread out names thinly across various niches we believe will make it. As soon as you start regging 100+ names in a single niche, especially if they arent top names, you are in trouble because when you make any sales, its only paying off the renewals from the last 2 or 3 years, its not profit, so investing lightly in various niches is the smart way to go because you are never go to sell 100+ names in a single niche...it just wont happen.
I try not invest more than 50 names in a single niche but thats just me.