Here's my take: Marner was a phenomenal player. He could help elevate others to become offensive threats. Remember when he got into the league and he was playing with Van Riemsdy and Bozak. He is one of the best Leafs the team ever drafted and developed. His regular season play has been amazing. Obviously, the playoffs are a different story. And, I feel that he got an oversized amount of the criticism compared to others in the core four. I mean, you can't slam Matthews, he's a generational goal scorer, Tavarese was a stud and free agent, and Willie...well, he got a lot of hate when he held out for so long...But, they all seemed to mostly disappear when the games mattered the most.
I think one reason Marner gets criticism is that his dad and agent argued that he was the equal of Matthews and deserved at $11M contract, which hobbled the Leafs with the cap. Now, if COVID never hit, the salary cap would have continued to rise, and it wouldn't have been such an issue for the Leafs. And, I think a lot of fans blamed him for all of that, despite him scoring 517 points in 416 regular season games (or 1.24 points per games) over that contract (though he only scored 46 points in 57 playoff games (or 0.81/ppg). BUT....I would point out that he scored over a point per game in the last playoffs (14 points in 13 games)
Now, that being said, losing Marner for Roy (or really, anybody) sucks. You cannot replace that talent. The only bright spot is the salary cap relief, but you need to actually use it to sign good players. Toronto needs a sandpaper dude with some skill. Like a Tom Wilson or a lower tiered Tkachuk/Sam Bennet. Guys that can fuck shit up but can also score...
Now, I have a weird feeling that Toronto is going to surprise people come the playoffs. I mean, I think they might just squeeze in, but could go on a shockingly long run...Now, would I bet money on that....no....But, it would be nice to see happen...
As for Marner in Vegas....I think he'll turn it around and start showing those flashes of skill and help elevate others. It takes a while to learn a new system and the tendencies of his line mates. I honestly wish him the best. I'm not thrilled about how he left things, but I also sort of think he resented all the negative coverage or bad takes by the fans about him. I honestly think he LOVED being a Leaf, but felt that he was the whipping boy. And, for that, I don't blame him for wanting a change of scenery.