Pretty sure MJ didn't.
There is this "lore" around MJ nowadays....but the fact is MJ was a bitter, bitter loser....perhaps one of the poorest losers in the history of sports.
Saying he wasn't means you likely ONLY saw him win or didn't see him play at all and are only speculating.
I've followed MJ since his NC days and have watched most of his games. I don't ever recall him not congratulating the other team. I don't know about Kobe, though. However, I can just see it now, the Kobe nut suckers, who will bring this up when the Kobe vs Lebron issue comes up. They'll say "if that was Kobe who just walked off the floor he would get crucified by all the LBJ fans". I hate to say it, but they would have a point.