Some of it is old habit — and form factor of course, as light and wireless as the OQ2 is, it's still magnitudes more "work" than just plopping on the couch and turning on the TV. But for me, the big thing is game quality. Other than dedicated rhythm games (basically, Beat Saber) or ports of successful non-VR video games (Skyrim, Superhot, Tetris Effect), very few if any VR games for the OQ2 (I do not have an Alyx-capable PC) feel more than a half-fleshed out tech demo, with the possible exception of multiplayer freemium (e.g. Rec Room).
I've basically bought every Oculus game with an average rating of 4.3 (out of 5) or more, and nothing has really hooked me. And I can understand the lack of fully polished/thought-out games given what I thought was a very small and niche audience. So I was genuinely surprised to see that 4M OQ2s have been sold...that's obviously smaller than a traditional console, but not at all bad for the first year of non mainstream tech.
I wonder what the active user/game purchaser rate is?
edit: actually since I've been very physically lazy lately, I get the most use out of my OQ2 by watching Amazon Prime video. The resolution is just barely good enough for an immersive experience, and the Prime app (unlike the very basic Netflix app), allows you to resize and reposition the screen exactly as you like.