The Spurs went from being a 60 something wins team with him, to a borderline playoffs team without him. The Raptors didn't sniff a championship without him, and won't sniff a championship without him anytime soon.
How good the Raptors did in the regular season without him doesn't matter. When the playoffs arrive (if they arrive somewhen) they will be missing that ultimate bucket getter and bucket stopper that is Kawhi. Because that's Kawhi's biggest strength: when the going gets tough, assholes get tight, ball movement stops and all the role players are there watching while standing still, Kawhi is the guy you want most to get You a bucket (or prevent one). Not Lebron, not Giannis, not Harden, not anyone. Kawhi, with that bot-like midrange jumper of his, is the one that gets done at the highest level in the NBA right now.