Big Sur effed up my 2019 iMac

Downloaded and installed Big Sur about a week ago. Was gone for 4 days over Christmas holiday and returned to a machine that cannot run.

Logged in at 9 am. Very slow and buggy. Tried opening a very standard application and got the swirling beachball. Restarted machine. Wouldn’t go to password / login start. Restarted again. After and hour it allowed me to type in password. Once that occurred another two hours went by before I could see my screen. But the spinning beach ball has been present entire time.

I have a 2019 iMac with far more storage space and ram than is standard.

Appears to me that warnings about bricking older model machines should be updated to include premium paid recent iMacs. This is ridiculous.
There are a lot of similar issues reported on the forum. My takeaway is that I'll wait a few more releases before switching to Big Sur.

have you read this:
https://developer.apple.com/forums/thread/651399

And checked you have not Avast installed ?
Big Sur effed up my 2019 iMac
 
 
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