The Shibuya incident is one of the most heartbreaking and impactful events in Jujutsu Kaisen. It all started with Kenjaku and his allies, Special Class Curse, plotting to imprison Gojo in the Prison Gate on October 31.
After that, many terrible things happened in Shibuya. The “Shibuya Incident” arc features some of Jujutsu Kaisen's most harrowing deaths and delivers some of its best fights. In this part, Sukuna takes control of Yuji's body after he is fed several of Sukuna's fingers at once. After taking over Yuji's body, Sukuna massacred many people and destroyed half of Shibuya.
Now, Jujutsu Kaisen fans are now realizing that Gojo, if he had taken this action, could have prevented the painful outcome of the Shibuya Incident. Specifically, when Gojo was cornered by Jogo, Hanami, Mahito, and Choso, he refused to expand his Domain and spared the lives of the civilians present in large numbers there.
This leads to Gojo being sealed, Sukuna taking over Yuji's body, and the deaths of many people in Jujutsu Kaisen season 2. Supposedly, if Gojo had used his Limitless at that time, his opponent would have will lose your life immediately. No curse, with the exception of Sukuna, has the power to endure Gojo's domain.
If Gojo's domain had ended the special level curses at that time, many tragedies could have been avoided.
First, he won't be sealed by Kenjaku. Gojo killing Jogo means Sukuna cannot take over Yuji's body and destroy half of Shibuya. That might also save Nanami from having to make a sacrifice. Or Mahito's death at Gojo's hands will prevent the departure of Nanami and Nobara.
Gojo's compassion, although noble, ultimately leads to many tragedies, and that is the irony of Jujutsu Kaisen. Gojo, the most powerful spellcaster of modern times, is a character not strictly bound by morality and compassion.
He is complacent, arrogant and self-centered. But inside he also has immense kindness that made him spare the lives of people who were not spellcasters, unintentionally destroying Shibuya. However, if Gojo uses his domain, he will no longer be the same and can subjugate the darkness within him, turning him into another Sukuna.
One user on Reddit summarized the consequences of Gojo using his domain then: “The calamitous curses will die, Gojo will confiscate Sukuna's fingers, Kenjaku will fail sooner, Nanami would be alive, the Zenin guy would be alive, the Zenin massacre wouldn't have happened, Sukuna wouldn't have gone on a rampage, overall the Shibuya Incident became an Inconvenience in Shibuya However, Gojo was inherently separate from everyone, this could start to push him over the edge.”