I have been using Mail for many years. Like OP, I have Gmail on own domain (in my case it’s the old personal G Suite offering). Additionally, I have a regular Gmail account and iCloud’s built-in email. Like OP, I did a clean install when Catalina came out (got a new laptop around that time).
As far as I’m concerned, Mail is one of those things that consistently just works. The only issue I used to have was quirky undo/redo of archivals/deletions, which I believe had to do with Gmail’s IMAP servers and/or the way Mail talks to them, but I am not noticing that lately.
If I were OP, I’d consider again whether third-party software that they and their coworkers have in common is wreaking havoc here. If there’s no such software or the issue manifests itself on a clean system without any third-party apps at all, then this Heisenbug should probably on Apple’s Radar…
As far as I’m concerned, Mail is one of those things that consistently just works. The only issue I used to have was quirky undo/redo of archivals/deletions, which I believe had to do with Gmail’s IMAP servers and/or the way Mail talks to them, but I am not noticing that lately.
If I were OP, I’d consider again whether third-party software that they and their coworkers have in common is wreaking havoc here. If there’s no such software or the issue manifests itself on a clean system without any third-party apps at all, then this Heisenbug should probably on Apple’s Radar…