Ashura and Indra were never equal. Neither were Hashirama and Madara, nor are Naruto and Sasuke. This misconception that, because it's yin and yang, that the inheritors of Ashura and Indra's chakra are equals needs to die. Odds are Ashura beat Indra in battle. There's a good chance some of Indra's reincarnations beat their Ashura counterpart over the ages. What absolutely isn't true is that they must all have been equals. That's just retarded logic I've seen forced by Sasuke fanboys that don't want to accept the fact that Naruto is stronger than Sasuke. Shocking, right? I mean, who would have thought the titular character is stronger than his rival? Yeah.