Because you are looking at it wrong. You are already taking the word, and putting them into the obvious link. Such as Superheroes also being average people too.
The Japanese version only says Comrade. There is no indication for it being RIVAL. Unless they speak English, only we see rival. There is no correlation to the fact they would be rivals, only to the one's that speak English.
Anyway the Boruto trailer-poster that just got released via Twitter Japanese says comrade only as-well. Link or nah?
All I see if you trying to justify that the instance where the word rival was used is a mistake. You just don't want them to be rivals because you dislike it.
Superheroes being average people is not even a comparable analogy. Those are opposites. It would only work if rival meant "enemy" exclusively which is the understanding that you hold that I was
trying to tell you that I don't hold. I do not think rival in this context means "enemy" and therefore your analogy does not even reflect my words accurately.
There are enemies, which are characters who oppose the protagonist and work to sabotage their efforts. What I have been saying since the beginning is that there are rivalries that do not fit that description. There are the type of rivals who are competitive. They do not try to win by sabotaging the protagonist, but by going on their own journeys of growth and improvement to keep up. Such rivalries can be had between comrades, and are a
staple of soooo many series in this genre that I think it's insanity that this conversation is even occurring!!!!
It's okay to have a healthy level of skepticism but there are times when it's not even important and just makes a person look like a party-pooper. This is not even one of those things where it makes much difference whether it's true or not.