27" 4K Dell Ultrasharp U2723QE display with hub function (i.e.: several ports), connected to Mac Mini via USB-C DisplayPort-Alt-Mode, and I got this dirt cheap as an open box special from Woot! late last year for $320.50 tax and all. I'm one of those people who don't notice an overt difference in evident resolution vs. 27" 5K (had a 2017 27" 5K iMac before this and compared side-by-side).
If I were buying today, I'd consider one with 120-Hz refresh rate, as I think they have a 27" 4K lower end option with that. I don't game, just heard it makes moving objects on the screen pleasingly smoother in motion.
Apple Studio Display is too expensive for me.
I'd like a Asus 6K 32" display, but it wasn't available then and $1,200 anticipated price (+ tax) is expensive.
Here's my thinking. I'm a home user, not making money off this Mac. There are too many fairly rapidly evolving frontiers in computer displays for me to want to drop a grand + on a display I might not stay happey with for 10 years because the 'new, shiny' stuff comes out later.
Yes, I know, 'new, shiny' always does, but there are times when development is evolutionary and times when it is revolutionary. These days in the fairly large desktop display space, I see serious trends...
1.) Faster refresh rates.
2.) Higher resolutions - more 5K 27" options, and 6K 32" options are coming out (aside from Apple's XDR, which at that price might as well not exist for me).
-----Right now 5 or 6K seems to equate to 60 Hz refresh rate, whereas both features are desired strongly enough individually I imagine many people would like to have both in one display. That will take time!
3.) Larger sizes going mainstream - it used to be 24 vs. 27", now it's 27 vs. 32". I'm not a dual display guy.
4.) OLED. But another forum member mentioned having heard text wasn't as sharp vs. LCD, and I don't see 5K and 6K options, so again, may take time to see how this shakes out.
For what I do with it, I'm happy with this Dell. Yes, I liked my former 27" 5K iMac's 5K glossy display slightly better...the Dell color in large white areas looks a bit 'warmer' (whether that's the color or the matte coating or both I don't know), and I'm disinclined to fool with color adjustments - not my comfort zone.
If I wanted 27" 5K today, I'd consider the Asus (around $800 last I checked) or ViewSonic (a bit more expensive but Thunderbolt 4 rather than USB-C). But for now, happy with what I got.