Representation matters.
GOOD representation matter more.
Just having a character be X doesn't matter if they're an awful character, or a horrific stereotype, and make that entire group look bad.
Like in One Piece. Compare the horrific transvestite giant headed stubbly monsters that chase Sanji. That's gross and rapey and if that's your first and only exposure to the idea, you're going ot think THAT is what all trans folks are like. And that's just… eww. But the series has Bon Kurei, Ivanokov, Inazuma, and more recently Kiku and Yamato. if THOSE are your first exposure to the idea, not so bad.
media has DECADES of very particular gay stereotypes to overcome. (And asian stereotyhpes. And black stereotypes. And...) Even super progressive Star Trek didn't get around to having main gay characters until like two years ago, when they could have been doing that in the 90's.
If Mineta was canonnically gay, he'd be the only confirmed gay character in the series, and he's awful and gross and wears a diaper and is a groper that mistreats women and just... ick. Straight men don't want that awful worst character in the series representing them, why would gay men?