Once again, that's not what Kishi was saying. Naruto himself expressed it:
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The point is, destiny CAN be changed.
You claim only people with special power got anywhere, yet all of those people play a role in the series.
Gai took on Madara and surpassed the genius Kakashi.
TenTen, Choji and Rock Lee were part of the Konoha 11 force that took down Juubito.
They also helped seal Edos, a critical part of the war.
TenTen also has the Sage's tools, which will play a big role later on.
There's also the fact that Obito was a loser, a non-genius, and became one of the most powerful people ever because of training.
You need to remember this is FICTION, a STORY, they are SIDE characters, they WILL get less attention than MAIN characters. What about Killer Bee, The Fourth Raikage, Gaara, Kisame, Sasori, Deidara, Kabuto and Kushina. None of them have been slated to be geniuses(Kabuto is a medical genius, but that kind of genius isn't what we're talking about), but they've played pivotal roles in the stories.