Look, this is a futile argument. The coach in Montreal now has to speak French (I believe it was the Bob Berry debacle that settled this). I regret it - but even more than that, I regret that this act of learning French has somehow become unthinkable, such that unilingual coaches are ruled out of court on the assumption that they can never learn a new language.
The argument that Vigneault is no good because he's 'recycled' is, to put it simply, just plain stupid. He was a good coach in the 1990s and he's an even better coach now. That's all that matters.
Crawford is also a good coach.
The argument that such coaches are 'no better than Therrien' may (or may not) be true, but this is not an argument for keeping Therrien. Even good coaches go stale after a while, and sometimes a team just needs a change, a new start. Most coaches who get fired are actually good coaches who just ran out of credit in a particular place and with a particular group of players.