>which is similar to the risk on the other side of the table

In principle but not magnitude, especially if you've relocated.

Usually you cancel any other pending offers once you've accepted a position if you're nice, and that could close some doors because someone else takes those jobs. Might even get you red-flagged if you go back to them and say "this company lied to me so I quit" (the other person has no way to verify that's true or you blew up on someone verbally the first week and got canned).

Someone correct me if HR can give the termination reason, I don't remember.