Playoff upsets are pretty common in the NHL. Which works both ways against the Leafs. Losing to Montreal, in isolation, is not a massive deal. It sucks, but upsets happen fairly regularly.
The problem is that over 5 years, they haven't won any upsets despite three chances to do so, and then they've lost two in which they were the favourites. So for simplicities sake, if you say they had a 40% chance of winning any of the Washington or Boston series, and a 60% chance of winning either of the Columbus or Montreal series, then just going by those odds, the Leafs should have won 2 or maybe 3 of those series (and even if you treat Columbus like a coin flip, you still end up in that range, though slightly more likely to only have 2 series wins).
But they lost all 5, with the last 4 going to a final deciding game. Leafs have had 7 games in which they could have clinched a series win in that time span. Here are the stats for Matthews/Marner in those games:
- Game 7 Boston 2018 - Matthews + Marner combine for 1 assist.
- Game 6 Boston 2019 - Matthews + Marner combine for 1 goal.
- Game 7 Boston 2019 - Matthews + Marner combine for 0 points.
- Game 5 Columbus 2020 - Matthews + Marner combine for 0 points.
- Game 5 Montreal 2021 - Matthews + Marner combine for 2 assists.
- Game 6 Montreal 2021 - Matthews + Marner combine for 0 points.
- Game 7 Montreal 2021 - Matthews + Marner combine for 1 assist.
So between the two of them, that's 1 goal, 4 assists (5 points) in 14 games between them, which the Leafs have gone 0-7 in. Our stars folding when it matters most is problematic, especially given that Matthews contract arguably values him as the best player in the league (given that his caphit is pretty close to McDavid's, but only on a 5 year deal) and Marner's values him as probably the 3rd best player in the league (based on caphit, term, and the fact that it was an RFA contract).