One Piece anime indirectly affected a major plotline of the finale saga.

SUMMARY

Fans were disappointed with the One Piece anime’s alteration of the Long Ring Long Land filler segment.

While many fans may be unaware, the Long Ring Long Land filler arc could be related to the final story.
There are several speculations indicating that the arc will be crucial to Luffy and Shanks’ confrontation.

An anime series as big as One Piece has a habit of introducing extra narratives to keep a valid distance from the manga story. This helps the anime maintain a satisfying pace that would allow the anime to perfectly animate each episode. Most of these changes are usually done in the filler arcs, which don’t affect the story as much.
Strawhats in One PieceOne Piece | Toei Animation
However, the One Piece anime’s modification to the Long Ring Long Land filler arc led to the disappointment of the fans. So much so that they even deemed the filler arc the most hated arc in the history of One Piece. The changes in the arc unnecessarily affected the length of the series and ultimately made it much slower than before.

While many fans might not know this, the Long Ring Long Land filler arc might be connected to the final saga. There are multiple theories that point out that the arc will play a major role in the confrontation between Luffy and Shanks.

One Piece Anime Butchered the Long Ring Long Land Arc

The Long Ring Long Land arc was a filler arc between the Skypiea Island arc and the Water 7 arc. In the manga, the storyboard of the arc is quite short and sufficient for the fans to get ready for what is coming in the next arc. However, to control the pacing of the anime, the One Piece anime series decided to extend the storyline by introducing unnecessary elements.

The arc was based around the prominent Davy Back fight among the Pirates, which allowed the winning team to gain a member from the losing team. In the manga, the Davy Back fight only had three fights, but the anime decided to add three additional fights. This made the arc boring and extensive, and fans evidently lost interest in the series.

Davy Back Fight in One Piece | Toei AnimationDavy Back Fight in One Piece | Toei Animation
Additionally, the arc puts Luffy in a moral dilemma, where he has to choose between his crewmate Chopper, and the horse, Shelly. While in the manga, Luffy chose Chopper without a doubt. In the anime, he decided to first free the horse from the clutches of the Foxy Pirates and then go for Chopper. This led to fans developing a hatred for the arc.

Theory Suggests Long Ring Long Land Arc Has Great Importance in the Final Saga

While the arc has become the most hated arc in the entire 1100+ episode anime series, many fans have theorized that Eiichiro Oda has used his foreshadowing skills and hinted at an important upcoming fight through the arc. The fight involves the two Emperors of the Sea: Monkey D. Luffy and Red-Haired Shanks.
Shanks and LuffyShanks and Luffy | Toei Animation
According to the theory, irrespective of their position as Emperors, Shanks and Luffy have a very deep relationship that kills every possible scenario of the two entering a fight. Shanks is the whole reason why Luffy became a pirate in the first place. Therefore, their chances of getting into a battle for the One Piece treasure are very slim unless Shanks turns out to be the villain.

Therefore, the best possible way for them to resolve their issues would be through the Davy Back Fight, which was the central theme of the Long Ring Long Land arc. It would not only keep their relationship intact but could also work as the perfect happy ending that Oda desires for his magnum opus.