That experience was almost 20years ago, between 2006 and 2009 (I had to check linkedin because I only remember which employer I was working for) so based on wikipedia it was still KDE 4 wich was very unstable.

I tried a few times KDE 5 over the years out of curiosity then more recently KDE6. I have it on one computer but I rarely use it as it is the gaming machine and I very rarely play videogames. The thing is I got so used to the ergonomy and shortcuts of gnome and i3/sway that whenever I use KDE I need either a lot of time to get used to the default keyboard shortcuts and layout and/or I need to take time to modify/configure it. But since I have been fairly happy with gnome and sway I don't really have much insentive to switch again. No hater really.