No, Indra lost the title as successor, not the main battle. As the battle was a war of feelings and ideals, rather than power and Hagoromo agreed with Ashura and not Indra. The main battle ended in a draw as far as we know. (As Hagoromo states that both their bodies were destroyed, meaning he can mean that they both died of old age, one did or none of them did.) However, we know that Indra and Ashura was decently equal in power and that was when it was:
Ashura + Hagoromo's power + his friends vs Indra
Madara and Hashirama were equally strong as well. Madara's goal was not to win, but to gain Hashirama's DNA and fight him for fun. If Madara had activated the Izanagi right away, then Hashirama would have died from his attack. When the battle ended, Hashirama was at the brink of death, and Madara died but had a way out of it. This logic also applies to Naruto and Sasuke, they are both holding back and they are both equally strong.
