> I think FPSes are popular on flat-screens because they specifically aren't realistic.
There is quite a few popular milsim FPSes which kind of favor realism (to a reasonable extent), both in in-game physics (weapon, vehicle and player body behavior simulation) and visual depiction.
I think FPS is popular because this is one of the fundamental genres out there: a depiction of a combat, as perceived by a combatant. This... err... trope has been there since the dawn of men, people imagining themselves fighting. The advent of 3D graphics brought that to computer gaming.
Adventure is another fundamental genre, and I'd disagree that it's niche. See below.
> [...] basically by definition, because if you don't try harder than the other guy, you die, so you have to try your hardest and hope it's enough
I'm sorry but I just don't understand this argument. This applies to every competitive game out there, no matter the genre. If game has this concept when the best performing player wins and other player(s) lose - you have to do your best.
> I've personally found the experience of simulating killing people in real first person view to be psychologically disturbing.
That's a problem unrelated to VR. Although it's somehow aggravated by it, as VR strives for more immersive experience, thus, more realistic depictions of in-game events.
I wonder if you should compare this to airsoft games. They provide a realistic immersive environment (in my perception, immersiveness the primary promise of VR), and they're sort of FPS-in-real-world stuff.
> stand the other people invariably get paired with in public multiplayer
First, I believe this has nothing to do with game presentation layer (like VR or even 3D at all) or genre. Second, there is an awesome solution for this: playing with friends.
As for the genre - I assure you, you can find less than enjoyable opponents in any game genre. Especially strategy games (MOBA/ARTS subgenre, specifically, hehe), but not limited to that.
> If VR could kill off the FPS genre
I don't think that's possible. Again, the advent of 3D graphics brought the genre to computer games, and you can't put the genie back in the bottle. VR - if it becomes mainstream - could transform the genre, but can't kill it. The fundamental idea of a simulated combat as perceived by a combatant is way too high-level concept.
Also, I'd disagree that your "adventure used to be one of the most popular and now it's niche" statement. Adventure genre concepts are still as popular as they always were. Storytelling, exploration, and puzzle solving are key elements of a lot of mainstream games out there. My understanding of what happened is the genre fusion, not a death. A specific UI design patterns (esp. those of point-and-click adventure games) became less popular, but I still wouldn't say they're gone "extremely niche".
> and cut out a huge swath of the most problematic portion of the gaming "community"
I'm sorry but this sounds really weird to me. My understanding is that our world doesn't work this way, so your idea feels strange. It's not like $genre games make people toxic, and if it's gone then those people just vanish off the face of the Earth. If the FPS genre somehow magically disappears, the desire to interact with others would lead them to other pastures.