One Piece: Why Fish-Man Island Is Far More Important Than You Think

gamerant.com:

Eiichiro Oda's One Piece is filled with great arcs full of adventure and incredible storytelling. From the likes of Arlong Park to Enies Lobby, Marineford, and even Wano, One Piece features story arcs that are truly magnificent in terms of writing and can easily be considered to be some of the best arcs in all of manga. While there is no denying that these arcs hold tremendous importance to the plot, there is one arc in particular that holds even greater importance to the overarching plot of the entire story, perhaps more than any other arc – Fish-Man Island.

The Straw Hat Pirates planned to visit Fish-Man Island after their adventure on Water 7 finally ended. However, the many detours they took ended up pushing this journey to after the two-year time skip. Once the crew reunited, they set sail towards the island and thus Oda kicked start an arc that is laden with clues about the end of One Piece and the final war that will eventually split the seas apart.

One Piece: Who Is Joy Boy & What Was His Treasure?

On the surface, Fish-Man Island seems just like your average One Piece arc where Luffy fights a strong tyrant and liberates the island, however, there is much more to the arc than just that. Among the many races of the One Piece world, Oda chose to focus on Fishmen quite a lot and the heavy persecution that they faced at the hands of the humans from centuries ago made them crucial to the overarching story. Fish-Man Island gave fans a look at the prejudice that humans have towards a race that's different from them and in a beautiful manner, Oda shatters the walls that separate the two races through Luffy and Jinbe. By sharing each other's blood, Oda showcases how Luffy will bring about the change in the world of One Piece