Isles are dirty as hell. 2nd year in a row they break the arm or hand of a Canes player with a slash. Of course, neither time it was called.
Islanders, especially one removes fighting penalties w/o instigators from the mix, have been consistently bottom of the PIM list for a very long time now. So people can keep saying that, and they can keep on saying it despite the evidence. I didn't see the second slash you are noting (the one on TT last year was a pretty unfortunate result of it happening during a shot follow through). But one alternate hypothesis, that perhaps the Canes should look at their player's choices of gloves, rather than the Islanders being especially dirty, is just as reasonable.
The only player I've seen the Islanders deliberately attempt to take shots on in the playoffs was Kucherov. And that mf completely deserves every bit of a Scott Mayfield crosscheck.
From an Islanders point of view, the absolute only chance they had was to dominate the goaltending matchup, and they didn't, Varlamov was pretty good, but not extraordinary. Sorokin, in his little time, was awful. Andersen was, for the most part, competent. Pretty good (& awful for 2 periods) vs competent in context of the domination of the puck by Carolina was not close to being good enough to give NYI a chance.
imo Barzal was great, and showed us again and again that his goal scoring is not limited by his unwillingness to shoot, but that his unwillingness to shoot was actually a reasonable choice based on his teammates being better at shooting. What's improved about his game, all year long, is that he's starting to grow into the defensive player he always had the talent to become.
