Obito killed thousands of people during the konoha attack, killed Naruto's parents, led the atrocious foundation called Akatsuki even though it was Yahiko who founded it, so he caused the other destruction of Konoha during the Pain arc, tried to steal all bijuus, started a freaking war ffs, killed thousands of shinobi once again, became the fcking juubi jinchuuriki. And you still think he was the only uchiha who could have been a kage, he may be awesome or cool as naruto said, but he definitely isn't worth becoming a kage