Hi.I'm facing issue similar to this one:
https://www.displayfusion.com/Discussions/View/delay-when-hovering-on-desktop-icons/?ID=00f874d5-c5c0-413c-98cc-3a4408e355ad
So this is probably not new. System is pretty powerful: RTX 3080, r7 3800x, 32gb of ram, Windows 10 21H1 ver. 19043.1023
I captured issue below with 2 gifs. You can see that when DF is running the response time of hovering over icons are not smooth and when DF is closed completely it returns to normal. I tried disabling several polling options, title bars, taskbars, triggers, icon profiles, monitor profiles basically everything but only completely closing DF is fixing this issue.
I can't tell if it really has any performance impact in applications like games but with DF closed hovering over icons explorer.exe uses 2% less CPU.

I also found out that disabling application hooks in advanced settings also fixes issue but with them disabled start button on second monitor not working

Displayfusion 9.8 running: https://i.imgur.com/U4SnBrI.gif
Displayfusion 9.8 not running: https://i.imgur.com/EPbeBcV.gif

Well disabling application hooks only for explorer.exe also fixes issue with lagging icons animations but start button stops working on second monitor with DF taskbar and unfortunately Microsoft after all these years not enabled tray icons on second taskbar so it basically useless for me.

Hi. Here it is

I noticed that on 1440p 120hz screen it's lagging more than on 1080p 60hz screen (also DF taskbar enabled on 1080p screen while default windows taskbar enabled on 1440p). But as I said before with DF closed or app hooks disabled for explorer.exe everything goes to normal.