According to J-Cast, the official BBS of Toei Animation has been filled with hundreds of complaints against the new OP theme song of "One Piece
". The audience resented that the new song was completely mismatched with the serious OP animation.
Toei Animation One Piece BBS
The new OP song "Kaze wo Sagashite" is a tie-up work with a TV quiz program "Quiz! Hexagon II" and the singers are idols and comedians. Toei Animation said it's usual to see such negative reactions when theme songs are switched. They don't plan to make any explanations to the audience and the new song is likely to be used for the next one year.