I disagree the jets were a much happier, more cohesive team. I think the Sharks will be as well.
Every NHL team the kane has played on in the past has deemed him to detrimental to keep on their team. His off ice antics have only gotten worse and from what has been leaked from SJ his on team antics have stayed the same since Winnipeg. I don't play professional team sports but i would most if not all players credit the "great room" for many winning performances. I imagine rallying a team between periods is less efficient with a player who expresses his lack of respect for his fellow teammates consistently (coming late for practices, ignoring team rules, etc).
It took the Jets three seasons to be a playoff team after moving Kane so even if they were more cohesive, it didn’t yield immediate results at all. They still needed to make quite a few moves to get there.
Buffalo was problematic even before Kane showed up.