I had an upgrade plan for my PC that involved a step up to a 4k monitor, but when the time came, it was hard enough just finding a 4k monitor with decent specs that I stopped to really think about whether I would really benefit from it. I already knew I didn't need it, but I realized that I wouldn't even really gain anything from it. I already used the UI scaling with the one 4k monitor I had at work, so that was a wash. And for games, I didn't really have any times when I wished the resolution was higher than the 1440p I was already using, but I did have times when I wished it would generate the frames faster or more consistently.
Part of the change was a new GPU to handle 4k better (they were supposed to justify each other), but I ended up just getting an ultrawide 1440p monitor instead.
I don't think I'll ever bother with higher than 4k for TV or 1440p for PC.
