honestly, I look at boston's core and it sounds good on paper but most of the players are aged. even pastrnak isn't young anymore.
I think that Montgomery fell in to the old trap. He massively overperformed with a mediocre roster several years in a row. Then when his team plays at an expected level, he gets fired. They think his coaching is the issue, but it more than likely is not. He had a couple of INSANELY good seasons on the Bruins rosters that he had.
Sweeney is the one that should be fired. The players are the problem.
And btw, if I was a GM of a struggling team, I'd seriously consider jumping the line and firing my current coach for Montgomery, because I hold him in quite high regard.