Jujutsu Kaisen's second season has been a smash hit, with the "Hidden Inventory" arc just reaching its conclusion, showing the events that elapsed in Gojo Satoru's past. This arc is one of the series' most important, as the tragedy of Riko Amanai started a ripple effect in jujutsu society - the consequences of which are still felt now. If Geto and Gojo had been successful in their mission, Geto might have remained in the Jujutsu world. Thus, he never would have turned into the villain he was in Jujutsu Kaisen 0 or later become a vessel for an even more formidable antagonist.
Source：https://www.cbr.com/jujutsu-kaisen-geto-suguru-jujutsu-sorcerer-anime/
