Basketball is the only major American sport where I really place a premium on winning team championships when ranking individual players because there's such little parity in the NBA. At the start of the year you can pretty write it in ink which three or four teams have any realistic chance of reaching and winning the Finals.
It's also a game where one elite player can have a tremendous effect on a team's success because there's relatively few players on the court at one time and a really good player will play practically the entire game. It's rare that the best team in the regular season doesn't at least reach the Finals, and the team with the best individual player is usually the team that wins in a seven-game series. Not always, e.g. when the Mavs beat LeBron's Heat, but usually.
For example if LeBron, Jordan, Shaq, maybe Kobe too, in their respective primes go to any team in the league, that team is immediately a Finals contender (well maybe not Philly this year but any other team
) and their old team probably struggles to even make the playoffs.
Contrast this with the NHL, where even the best forwards only play like a third of the game and you can ship Wayne Gretzky at the height of his ability to the Kings and they never win a Cup. Or the NFL or MLB, where the team that wins the Super Bowl / World Series very often is not the best team in the regular season, does not have the league MVP, and one player no matter how good can't carry an otherwise average team to a championship.