iCloud conflict with quicklook

iMac (Retina 5K, 27-inch, Late 2015), OS Monterey 12.7.3 (formatted apfs), using 200GB paid subscription to iCloud+

Since Big Sur, iCloud just does not work well at all. Everyday is a struggle. Multiple times per day, Finder stops working and the whole system stalls. And yes, I have started over several times with a clean install, first wiping the hard drive, etc. The issue persists in Safe mode, etc...

But I can muddle through the day by dong the following every couple of hours:

1. via Terminal, qlmanage -r cache
2. via Terminal, qlmanage -r
3. via Activity monitor, force quit com.apple.quicklook.ThumbnailsAgent
4. empty trash
5. via Activity monitor, force quit bird

After about 30 minutes of:

iCloud begins to sync new files, and I can again use Finder (for only a couple of hours, and I repeat the above).

I can only logically deduce that since Big Sur, all system files and folders, including Mobile Documents/iCloud, are protected, and thus cannot be addressed by quicklook and/or thumbnailsagent (and yet, thumbnails agent never gives up and never surrenders in its 24/7 mission).

I have zero issues with my MacBook Pro OS Mojave... works like a charm...

I probably have in the neighborhood of 250,000 files stored in iCloud, ranging from art and font assets as well as design and office docs. I pretty much depend on iCloud to mirror all files on multiple computers.

Any suggestions would be deeply appreciated.

Thanks.