I disagree. I think McConnell and the rest of the GOP establishment want Trump gone for good, and an impeachment conviction is the first step in that.
Agreed. I'm thinking that McConnell's calculus includes "So what if we convict or get close to doing so? Where else are Republicans going to go?". He sees little downside to conviction, and what negative effects there are can be remedied in time for the 2022 elections.
He may be right in some respects. It's also reasonable to consider that some Republican voters will just "check out" and be more engaged in elections locally and at a state level.
Unfortunately, I believe President Trump made an unforced error re: the 01/06 meetup. It seems that Senator McConnell is about to make an unforced error as well.