So out of Street Fighter and MK, KoF was his inspiration? That's new. I mean SNK fighting games like World Heroes, Fatal Fury, Last Blade, etc ruled the 90's. I can't be too surprised.
Well Street Fighter pretty much invented the fighting game genre, and the mechanic to cancel the animation frames of one move into another (which was a bug, so it was invented by accident), so that's obviously the inspiration for every fighting game in some way.
But some of the more rare characteristics of Smash were first demonstrated in SNK games. So hearing that Sakurai was playing KOF 95 while he started thinking of the concept of Smash, it makes sense why those mechanics are in there.
If anything, it's cool to know that Sakurai was a fan of those games, and even doing advanced combos.
Because Sakurai was (supposedly) against the competitive play styles of Melee, and added a random tripping mechanic to Brawl to prevent it, I was under the impression that Sakurai didn't like and didn't play competitive fighting games. But hearing his KOF story, I understand that the intention didn't come from him disliking those games, but that he wanted to create a game where people wouldn't get overwhelmed as easily by more advanced players, and still manage to have fun.