Nothing is random in a story, bro. The only reason Hashirama was given this earlier is that he is not the hero. Concerning the hero, you want him to suffer before getting anything. You want the hero to struggle until the very end. However, one thing is certain, and it is that the hero will reveal new powers every single fight, and the greater the opponent, the more power the hero discovers in himself.
My opinion is that Ashura got the body of the Juubi (wood source) and Indra got the eye of the Juubi (Sharingan). Basically, both Hashirama and Naruto have chakra similar to Biju chakra. Do you remember Hashirama's necklace? Everyone who worn it apart from Tsunade died, and only Naruto was compatible. This was the first time Kishi connected Naruto to Hashirama.