I had 30 min in a certified helicopter simulator earlier this year.

The sim was built out of an actual fuselage (Sikorsky S-76) with full controls, visuals were 8x projectors on a curved wall in front of and around the cockpit. Everything was bolted to the floor, no movement anywhere.

After 10-15 minutes I did a hard bank and my gosh, the whole world moved, and I could have sworn I was about to slide out of my seat. I panicked that I didn't have a harness on.

The instructor laughed and said that was quite normal and that many people get very motion sick.

So yeah, I can see that motion sickness, with the "right" setup, could easily be a thing.

Maybe not motion sickness, but I’ve yet to wear a VR set I can enjoy for more than 10-15 minutes at a time. I think some people just adapt to stereoscopic illusion better than others- I struggle during 3D movies too.

There is a small fraction (iirc 10-20%) of the population for whom a disparity between accommodation (focus) and binocular vision (what 3d movies do) causes headaches and nausea.

This is why most 3d movies have very little happen in the virtual space between you and the screen. Since more than about 7 meters away is basically all the same final distance, it's fine.

That being said, it's the stuff flying at you that makes 3d seem worth the extra money, so they try to balance it. Some people will still get very ill even with the small amount that movies do.

Technically, https://en.wikipedia.org/wiki/Virtual_reality_sickness, but I think motion sickness suffices as a generic term.

I also think discriminating between motion sickness, flight simulator sickness and virtual reality sickness is splitting hairs, or at least a gradual difference. One could claim motion sickness requires real motion, but you have that in a good flight simulator, too, and most VR setups allow one to, at the least, move one’s head freely.

The term “motion sickness” describes the disparity between sensations that the mind expects to accompany what the eyes are seeing, but those sensations are not there. In a flight simulation, things like gravity, acceleration, etc. are not really possible to simulate.

The physiological basis is that a disagreement between the inner ear's sense of balance and the eye's perception of orientation is an early signal of having ingested a neurotoxin. Thus vomiting to expel whatever you just ate is a good first response.