KDE is SO GOOD.
I've distro hopped and DE hopped a lot before settling, but it's been amazing for me as somoeone who has switched over from Windows. It just doesn't get in the way, is super familiar for me, AND lets me do a lot of things I wish I had in Windows.
I was worried about the "choice fatigue" due to it being super configurable and all, but honestly the defaults are so sensible I haven't really had a reason to tinker with it much if at all.
+1. I switched from Pop OS to Debian + KDE last week, and KDE has been solid. I too read a handful of articles calling out the choice fatigue, and other than a few tweaks (maybe half an hour?) I was ready to go. I run old-ish hardware (circa 2013) without any issues.
Something notable is that the all the hotkeys felt 'just right'. I had to tinker a bunch in Pop OS to get satisfying hotkey combos, and the COSMIC upgrade reset them all.