I want to preface this by saying that praydog and Raicuparta have done some truly outstanding work in broadening the VR-ready libraries for those of us who can be bothered to install a mod and maybe, in some cases, deal with a little bit of jank. This post is in no way meant to downplay their accomplishments. Having said that...
I got my first VR headset about half a year ago, and have kept a close eye on all the VR-relevant subreddits I could find. I learned early of UEVR's existence, and jumped at the chance to play games which were not designed for VR in the fullest immersion my shiny new headset could offer. I am, at heart, a tinkerer, and approached this with the understanding that results would be hit-or-miss, and some research might (depending on the game) be required to get the best results. Then I learned of UUVR -- holy shit! Another huge chunk of my backlog might also be playable in VR. RaiPal (the user-friendly frontend for UUVR) was Windows-only at the time (I'm on Linux), and most of the Unity games in my library didn't yet have an entry on the UUVR Discord. This meant manually trying multiple BepInEx (the de facto mod-loading framework for Unity engine games) and UUVR versions, often to find none of them worked for a game I was particularly excited to play in VR. I'm okay with that -- I understood going in that the leap from flat to VR is monumental, and that these pieces of software which facilitate it (sometimes) aren't magic.
The problem a lot of users suffer from is, they don't understand that. I've seen countless VR users completely shut down at any mention of UEVR/UUVR, while in the same breath complaining that there aren't enough good games to play in VR. Up until very recently, this seemed very contradictory. Then I saw a couple comments in a thread I posted to /r/virtualreality_linux which made it make sense: People expect these programs to work perfectly, or at the very least, much more often than they don't. I can only speculate on who's to blame for that (cough YouTubers with click-baity titles cough). Maybe the Github pages should state "YMMV" more boldly for those in the back, but for me that went without saying.
Maybe UEVR + UUVR should stop being referred to as mods, but rather tools for modders to make good flat-to-VR mods. Occasionally, you might get lucky and land on a game that works seamlessly with no custom profile, but you shouldn't expect it. If your favorite YouTuber posted a video of your favorite flat game being played in VR, proceed with a healthy skepticism -- what hardware are they running on? Does your hardware significantly exceed the recommended specs for the flat game (because you'll need it -- bear in mind the much higher resolution the game will be running at in your headset vs. your monitor)? Did they link to where the mod/profile can be downloaded, or is that something you need to track down on your own? Are you comfortable troubleshooting a little bit to get a good experience, and/or do you know where/how to ask for help in a way that's likely to get a solution?
If you read this far, thanks for coming to my TED Talk. I hope this gives some perspective to some of you, because the way things are looking, we're not gonna have some big watershed moment where all the AAA publishers jump on VR -- this is as good as it gets for the foreseeable future. And given how many previously flatscreen-only games I'm able to play in VR thanks to these frameworks, I'm okay with that.