Wano had panels showcasing old women about to commit suicide, murder of people through ethnic cleansing with the Kurozumi. Orochi burning to death. The story is mature, the writing is just strained because Oda is trying to do so much at once.
Of course a manga sold to teenage boys is going to cater to teenage boys. What, do you want them to put giant robots in Soap Operas?
It's a pirate manga about a kid whose dick can stretch and who asked a skeleton to join his crew without knowing anything about him. Just because Oda isn't writing the manga the way you want him to doesn't mean he isn't taking it seriously.
The dude has spent 20+ years of his life making this series into what it is. Why the fuck should he care what I want?
99% percent of One Piece fans will never know this site exists nor care about it, why in the fuck should Oda listen to us? You can read this manga for free online. No one is taking anything away from you.
If it pisses you off that much, drop it and do something else. There are a shit ton of great series out there that you can also watch/read for free (depending on your views on piracy, in some cases). Oda's NOT going to change at this point, no matter how much we complain.
I hope you find another series you like, and that One Piece's pacing and writing get better. Also, honestly... how many "adults" on WorstGen act like mature adults?
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We're grown ass fools attacking each other over fictional numbers on bounty posters and which fictional characters are going to sail on a pirate ship. There's a reason my avatar is a clown, yo. Even if 1057 pissed me off, fuck staying mad about it.