A lot of Leaf fans don't put 2 + 2 together ..
The excuse is we simply got "outgoalied" and too bad so sad we lost, nothing we could do differently..
However when the opposition hold Matthews and Marner in check and goalies post low goals against is because Coaching is a major factor in the outcome of both system, strategy and motivating and preparing your team, and adjusting during a game to address them.
We have discussed systems earlier this year where opposition collapse back in their own zone forming a tight box around their goalie, blocking shots, clearing rebounds and keeping the Leafs on the perimeter. That is a coaching system.. Similarly if a coach sets up a natural zone trap/ left win lock and breaks up rush attacks and neutralizes a teams speed, which Leafs fuels their offense. That contributes to being "outgoalied" and Keefe has to deploy systems that exploit and breakdown that system which dictates game play and flow.
If Matthews and Marner line is not scoring and getting shutdown then break them up and try different combo's and use last change to get them away from their checkers etc. Simply giving them more and more icetime against a successful defense strategy isn't the only coaching option available. If the other team holds AM and MM to 1 goal in a series then that isn't just on them either, as it emphasizes strong coaching by the opposition to achieve that desired outcome.
Fans that think "offense wins championships" see a highly skilled Leafs roster and when facing a "defense wins strategy" its not coaching its simply the other teams goalie beat the Leafs, that seems to be the ONLY reason to explain away the loss.