>>284803135
It has very stable if small player base. It definitely deserves a slot just on the merit that there is still nothing out there like it and it has many different use cases.
I'd also add Anyland which is a good bit of fun to play around with. 
Those along with VRchat pretty much run the gamut of worthwhile metaverse style games. I can't really recommend Mozilla hubs since there isn't enough content there but could put it in an honorable mentions section. With some others that aren't complete garbage.
There's no reason to really parse down the rec list to core games only. I think it should have everything essential that someone new to VR should consider trying out.