Wikipedia: https://en.wikipedia.org/wiki/One_Piece
Anime News Network: https://www.animenewsnetwork.com/encyclopedia/anime.php?id=836
So, being as that I write about pirates, I would be remiss not to mention probably the most popular piece of media in recent memory related to pirates (and, incidentally, the most popular manga series of all time). That piece of media being One Piece.
That being said, I cannot in good conscience recommend One Piece, as I have a fairly low opinion of it. I hate the art style. I hate that it’s been meandering its way through its storyline since 1997 and not apparently resolving anything (though, I can’t blame the writer for that; if I was writing the most popular manga of all time, I’d do everything I could to keep it going for as long as possible).
That being said, I also can’t in good conscience entirely dismiss it out of hand. I haven’t bothered to get into it, beyond a very superficial viewing of the first few episodes of the anime. But it’s been running since 1997, has something like 900 anime episodes and 93 manga volumes (which translates to something like nearly 1000 individual chapters). I don’t have enough familiarity with the whole thing to know if it improves at any point. Maybe it does.
Clearly, it’s doing something right, if it’s made $21 billion (with a b).
Long story short, look into it for yourself and make up your own mind. I’m not going to fault you for enjoying it, I just have too many reservations to do so myself.