Shonen is the most popular anime genre because it is generally aimed towards teenage boys and young adults. That means that most Shonen series feature a good amount of fighting. At one point in time, the anime world was dominated by One Piece, Naruto and Bleach – otherwise known as "The Big Three." These three Shonen became massive hits because of their action scenes, and several of those scenes set the bar a bit too high thanks to their stellar animation and effects.
Source:https://www.cbr.com/best-big-three-anime-fight-scenes/