Changing mouse polling (e.g. using Piper) has fixed this issue for many users.
Nvidia driver 525 or mutter updates in gnome might also fix this issue which seemed to get worse in 22.04 (see the last comments here).
I did both the /etc/environment change as well as the polling change, and restarted. Not sure what fixed it or if it is truly fixed, but right now it feels ok.
Edit: Leaving the other solutions up, as they have worked for others, but for me... right after doing this, I opened slack and discord. Then I noticed the issue was back.
closing discord resolved the issue, opening discord then brought it back.
looking it up, it seems that disabling advanced > hardware acceleration is a thing, and seems to have actually fixed the issue, thank god.
crossing fingers, but I really think I nailed it now that I was able to reproduce it so consistently. Didn't realize it was discord since I just always have it running in the background. I suspect it was attaching to the wrong GPU or something? No idea, but jeez, terrible that it can cause every other windows to lag while dragging, what thing.
edit a few days later: the issue is indeed solved for me, this also substantially reduced my CPU usage, which often showed the temps completely maxed out even though the processor and gpu did not show high utilization--I presume it was the iGPU that was being maxed out? anyways, just giving a follow up here.