Agreed that championships should not be the only deciding factor in who is or is not a great player. But championships do define clubs and teams. If team A has 4 championships, and player A wins 2 championships as a player and coaches the team to victory in a 3rd championship.... He has now collected 3/4 of all championships won by Team A.....
Except in the rarest of cases, championships define teams, not players. In hockey, Gretzky and Orr. Brady and Bellichick in football. Quite a few in basketball. No one in baseball, unless possibly Ruth.
I might have missed a few, but I doubt it.