Old thread but forgot to update it: there’s no native way to disable VR. I finally wrote a feature request recently asking for this, so hope it goes somewhere. I straight up don’t want users playing with VR in my experience, it doesn’t fit the scope of my project.
Took too long but thanks to the people who replied here originally telling me I should.
Replying to provide a new answer that there is now an option in the access window of configuration to disable VR as a supported device, so now we do in fact have a native way to prevent VR use. I don’t know the extent of the option as it’s still new but here’s to hoping VR becomes completely unusable in-experience if it’s turned off. That’s exactly what I’ve wanted.