This is the understatement of the century.
I couldn't tell ya. I've never watched even a single episode of One Piece. However, One Piece fans seem to stick to one thread instead of having 5 One Piece threads on the front page, unlike Naruto/Bleach/Soul Eater fans, so I leave them alone with what they like.
Also, I doubt that One Piece is that shitty. It must easily be the best of the lot. I'm only trying to help people by warning them about how shitty Naruto/Bleach/Soul Eater are.
A man that has eaten shit his entire life might grow to find the taste OK, or even delicious. That doesn't mean that he isn't eating shit, though.