Actually based on greed, more greed, and some more greed.
Everybody wanting to buy the latest and greatest, at any price, to get into the game and of course, resell to someone other fool for a higher price.
True, not as many endusers are people believe there are.
Heck, see vr threads, marijuana threads, etal here...
Everyone waiting for a big payday to come when the endusers need to buy their domains!
When domains in a niche get to a certain price point, with no endusers, even resellers back down until the prices start dropping and dropping.
Ah well, the domain game is a crap shoot and like most crap shoots, more will lose than win.