There is absolutely loads of information on the internet about the possible effects of VR on eyes and brain etc. I suggest you continue with your own research and come to a decision whether you want to continue with VR or not.
I consider myself a "lay expert" on this, since I am legally blind. The short answer is "No," it is not bad for your eyes.
When Oculus headsets first came out, I was wondering if I'd be having the same problems I do with 3D movies/TV. Because each eye is presented with its own display panel; there is no issues in that regard.
The focal distance of the headset display is approximately 1.5 meters (4' 11"). If you need glasses or contacts, in real life to clearly see objects at this distance, you'll need them to see clearly in VR; or else purchase optional prescription lenses for the headset.
The Quest has an IPD (InterPupillary Distance) adjustment. IPD is the distance between the center of your pupils. For older adults, IPD adjustments are a comfort thing; but for younger users, an improper IPD adjustment could result in the user becoming cross eyed.
Someplace, buried a few dozen pages back in this forum, is a debate over the effects of "blue light" emissions. As an engineer, and a visually impaired person; this blue light stuff is bunk. The Quest uses OLED displays, which are easily damaged by UV light. Any blue light that is dangerous enough for you, would cause the displays to self destruct first.
On the issue of eyestrain; this is mostly an issue for binocular (2 eyed) users. Because your eyes are focusing on 2 separate displays, with a proper IPD; it should not be the same, as if you were using a computer monitor, and forcing both eyes to stare at one screen location. Besides, the battery limitations of the headset would force you to take a break now and then.
Oculus Rift CV1, Valve Index & PSVR2, Asus Strix OC RTX™ 3090, i9-10900K (5.3Ghz), 32GB 3200MHz, 16TB SSD "Ask not what VR can do for you, but what you can do for VR"
