So thinking he is good is overrating him?

You havent even said whats bad of him, what songs do you dislike? He has lyrically been praised ALOT, and for good reasons.
And virtually everyone in the industry are friends with Jay Z. Nas didnt only say good things of him, they are close friends nowadays. VERY stupid reason to hate on Lupe. Jay Z and Kanye are supporting a talented rapper with the right approach, because they are fan of his creative talent, and they have a vested interest in that Hiphop is represented by rappers like him.