Now that's where you are totally off base.
While Kobe, LeBron, Durant, and of course Jordan can move really quickly and change directions well FOR A BIG GUY, no way can they stay with the KevinJohnsons, IsiaThomas's, CrisPauls, or TonyParkers in the game.
The reason you see the big guys blow past the little quicker guys is the hand check and body check before the move. Push a guy 1/4 step back, you're free to move past.
A little guy blows past those big guys, but the big guys hand check, reach in, and body up the little guys when playing D.
Look at the size of NFL cornerbacks. NOT ONE, who's a coverage specialist, is over 6' tall, and most are closer to 5'9" tall.
NFL draws from a pretty big pool of athletic talent.
While RandyMoss and LarryFitzgerald can run as fast and jump higher than any CB, they need a preplanned route, while the CB is adlibbing and constantly changing his direction to REACT to the reciever's moves.