if we had a kid like Kotkaniemi I would not want to be swapping him out for a 25 yr old Dvorak. I also wouldn't want to be paying Kotkaniemi $6m for just one year, either. Montreal is in an ugly spot right now.
Yeah I think you hit on exactly why it was so effective as a revenge offer-sheet. It truly put Montreal in a lose-lose situation here.
If they match, they pay the player way more than they wanted in the present and probably in the future due to the QO issue. Not to mention the big off-ice distraction.
If they let him go, they're really not getting the return they'd want at this stage. Sure, Kotkaniemi could really fail to progress and in hindsight it may look like a good return, but there's no question that they didn't want to be forced into this "take it or leave it" return. Not to mention the pretty brutal optics of basically getting revenge-mugged for your recent #3OA center.
I don't totally understand the move in terms of making Carolina better, but I think it's pretty genius in terms of making Montreal worse.
I'd let him walk too, I think the alternative is worse, but it's still not a great scenario for Montreal here.