At the risk of sounding like a pixel and framerate crack junkie
I recently, over the last few months, went through the journey from single-screen (1440p 34" 21:9 100Hz) to VR (Rift S 80Hz) and now to triples (1440p 32" 16:9's 165Hz). On a 2080 super.
The single UW was great but setting it up was a compromise between a realistic FOV and being able to see enough of the track to look to apex in tighter corners, not to mention side to side (crew chief is a life-saver).
VR is totally amazing and 500% better than a single screen but the lack of resolution on 'affordable' displays left me a bit wanting. Since most of the time your vision is trying to look for reference points far into the distance (represented by only a few meagre pixels, it felt like a low-res experience compared to the single screen). Reading text/dashboards while driving was difficult, and the field of view was also quite narrow, so your peripheral vision is not fully utilized. It's not unlike wearing a helmet though, so it suits the driving sim experience. And, you can literally look everywhere so if you want to pull exorcist-like maneuvers to look behind, you can. I also couldn't comfortably use my over-ears headset, so I was also losing part of the audio experience (which is one of the joys of R3E).
I'm only a month into using triple screens and now that I have properly configured the FOV (screen angles, viewing distances, bezel correction, horizon height, and appropriate configs in the sim), I am thoroughly happy with it. I'd rank it as achieving 90% of the VR experience in terms of immersion (so, ~450% better than a single screen). What you give up compared to VR (more accurately simulated depth perception) you gain back in MORE PIXELS! to detail the areas of track you are looking at. I have also oriented my screens to achieve a 170° hFOV so my peripheral is fully utilized, which helps with awareness of where you are on track (the depth part). Looking left/right during the race (using my neck, instead of a button) also feels more natural, like in VR. If the FOV isn't set up right it will feel a bit flat, and possibly like you're in a Halloween "house of mirrors", but once dialed-in it is quite impressive.
In both VR and triples I had to turn down settings compared to the single UW, but with the right combos you can retain enough detail elements (shadows) to keep things looking pretty. Sustaining 100-130 fps in R3E which appears butter smooth.
All that said, once 8k 250Hz 180° FOV VR becomes commonplace I don't think triples will stand a chance. But I'd vote for triples until that day comes.