While some people will never be able to handle VR, the choice of equipment can have a massive impact on the comfort of the user. One of the worries repeatedly expressed by people on subreddits such a /r/vive|valveindex is that companies releasing cheaper, less capable headsets "poisons the well" by convincing people that VR just doesn't work well, or makes them sick etc. Believe it or not, some people claimed VR was dead in the water and a gimmick after trying the Google cardboard.
In the case of the Quest, it has several issues:
1. Hand tracking - using cameras on the headset means it's easy to occlude your hands leading to un-tracked areas
2. Compute Power - You need a really powerful GPU to get the most out of even relatively complex scenes. I have a GTX 1080ti and will probably upgrade to a 3080ti when these are released later this year. It's not overkill. The Quest was at first standalone. Unless you're strapping a large power supply and a GPU to your head you're not getting the power you really need.
2. It operates at 72 Hz - Research that companies like Valve have done (they've been working on this stuff a lot) has shown that refresh rates are a huge component in the sense of realism felt, and importantly sickness. The Oculus DK2 was 75Hz (ISTR). The Vive was 90Hz because it turns out people het less sick at 90. The Index is 120Hz with an experimental 144Hz mode, because the higher you push it the less people get sick, and at the very high resolutions people feel more "attachment" to the scenes they see. 72Hz is woeful.
3. Head tracking - The inside-out tracking method the Quest uses is (anecdotally, from user reports over time on reddit) inferior to the lighthouse style outside-in tracking of the Index. Knowing where your head is is very important to not making people feel ill, so better tracking here is critical.
Points 2-3 there are critical for your comfort, and the Quest just doesn't do VR justice. Sure, some people handle it fine, and the "real" equipment (and Index and a PC powerful enough to drive it) are substantially more expensive, but it would be unfair to bucket all VR after an experience with only the Quest.