An excellent point, but technically the Shadow Clone Jutsu isn't exclusive to Naruto.
Hahaha! You're so right! I rewrote that sentence in my text and left off the part, 'he's the only one that can do it really, really well.'
But you're right - others can do it too, and are very good at it. Naruto just has them beat by volume.
And yes, Sasuke is the one who is the real loser here. And no matter how overpowered he gets, that will never change. His jealousy certainly has increased tenfold. And I bet if Naruto hadn't set his goal on becoming Hokage, Sasuke wouldn't be nearly as interested in taking over that position. He would have moved on to some other country and never looked back. But underneath it all he's still locked in the grade-school battle with Naruto.