That's a factor but there's many and they can vary from person to person. For some the lens type is an issue, for some people it's simply inability to get it to fit your face properly.
The frame rate doesn't matter if I start moving with a controller while I am sitting down IRL. I don't get the motion sickness if I have to actually walk to move in the game, but the disconnect between moving in the game not matching the movement of my body is what really causes motion sickness for me.
But that's something you can get used to, I fly FPV drones and that feeling was overwhelming in the beginning (way more intense than any VR I tried), but if you keep at it eventually you get used it.
I kept at it for 5 years; I never got rid of that kind of nausea. Only the nausea induced by the visual effect which I had even just playing, like, Work Simulator, at first.
For me it's the way the motion trackers map head movements, somewhat depends on how it's implemented in the game, but there's a way I can move my head that will give me instant nausea in any VR game. I'm not predisposed to motion sickness either, fine on rollercoasters etc.