Interesting, I'm on 3x27" 2K monitor (same setup as you, portrait, landscape, portrait) and while it works very well for me, I'd like to replace it with just 1 screen (or 3x 4-5K monitors but that is less interesting to me). I already have custom window management software that I use so it wouldn't be hard to switch to sub-dividing 1 monitor to get a similar experience (I think).

Maybe I should look into the 40" 5K monitors, thanks!