When a new "App" is installed on Big Sur (and I think this was on Catalina too), there is a check to see if the developer ID has been tagged as providing malwar

When a new "App" is installed on Big Sur (and I think this was on Catalina too), there is a check to see if the developer ID has been tagged as providing malware. When Big Sur launched, there was a glitch and the servers hung, leaving a lot of users in a bit of a lurch. It's easy to disable the check and a lot of software never gets checked for other reasons.