Are we talking about "DIR divers" though or "DIR divers who refuse to dive with non-DIR divers"? I consider myself the former, but have yet to meet any of the latter kind.I feel like a lot of the Tech / DIR / GUE stuff is gatekeeping.
It's a matter of "are you good enough to dive with us"
When diving in a "team" or buddy pair, I will absolutely make a determination if the person I'm diving with seems to be a safe person to dive with. I hope everyone does that, DIR or not. That determination is situational -- I don't mind diving with newly minted PADI OW divers at the local shallow dive spot, I think it's fun to show new people around. Not much DIR involved, and still perfectly safe. However there are other deeper, more complicated dive spots where I know that there are certain people I would not dive with and quite a few I would -- again, not a lot of those are DIR per se, but they're certainly good and dependable divers and that's really all it boils down to. The more complicated the dive, the more I think it's nice to share a set of routines, equipment, etc to make things run smoothly. Is this gatekeeping? Sure.