I wouldn't say One Piece is sexist. I would, however, say Dragon Ball is sexist. In One Piece, female characters get shit done. In Dragonball, the only reason for their existence is to be ogled and show pantsu/tit jokes. 'isms' such as racism and sexism are about intent.
You can say "all the women in One Piece are either super models or ugly", but can't you say the same the exact thing about the male characters? The biggest difference is how they are drawn, and that's mainly attributed to the fact that Oda can't draw women very well.
Zorak says the male equivalent would some dude's junk bulging out of his pants, but I don't think so. I remember when One Piece Musou was revealed, these fangirls in the audience creamed their pants when Zoro turns around to be slashed by Mihawk.
To be honest, I'd much rather have a female's perspective, than another white male on the internet has a victim complex who has probably never been discriminated against in his entire life.
