Windows Update cleanup not working?

Maybe I have the wrong impression of Cleanmgr+ capabilities. I've had this problem for a while now.

For instance, I just installed the latest Windows Updates, including "2022-01 Cumulative Update for Windows 10 Version 20H2 for x64-based Systems (KB5009543)", but after running a Cleanmgr+, which included Windows Update Cleanup, it only found about 10mb of stuff to remove.

I had to go to my Storage setting >Temporary Files, where there was still over 4gb of stuff to get rid of, including 3.22gb of Windows Update Files. and about 700mb of delivery optimization files.