This is literally the only truly important part after a certain threshold. I have a 34”, 1440p monitor and the text is noticeably better than any 1080p screen. It’s entirely legible and 4K would not provide a new benefit except maybe a lighter wallet. It’s also 100Mhz which is again beyond the important threshold.

The only time I can see 4K being essentially necessary is for projectors because those screens end up being massive. My friend has a huge 7’ something screen in the basement so we noticed a difference but that’s such an outlier it should really be a footnote, not a reason to choose 4K for anything under 5’(arbitrary-ish number).