My boss didn’t need Recall to do that to me a decade ago. He called me out for going offline in our messenger app for an hour after lunch while I was helping another tech sort an emergency for a client from their machine.
I told him that’s fine, I’ll just let everyone know that I won’t be assisting and will show them that email every time anyone asks. He backed off, but not everyone is going to get that lucky to have a complete moron who is going to put dumb shit threats in writing without running it by anyone in legal, HR, or their own boss.