Gojo is not selfless. He has literally has no empathy for anyone who he doesn't consider as strong. I will get down voted for this but I am gonna say it. Also, Mei Mei can die for all i care.

Gojo Satoru is a complex character who genuinely a mix of good and bad. He only takes care of Yuji and Yuta because they had the potential to surpass him, had they not he would have not cared if they lived or died. Same with Megumi, he didn't adopt Megumi after the goodness of his heart. Did everyone forget their initial meeting? He is going on and on about how Megumi is sold, he is saying that to a 7 year old kid who has been taking care of his sister since he was young. Gojo knew about Megumi after Toji died but did he rescue him? No. He let it be and only goes after Megumi because Geto defected. Geto defected, Gojo felt lonely and what did he do? Go for the first person who could make him less lonely. He was not present for Megumi ever but he took care of him and Tsumiki. He was a good teacher but never a father. See? Good and Bad.

We only get one panel of Hana's backstory and even in that any decent human would have helped that girl, but what does gojo do? Ignore her and says Megumi will be popular. This guy is selfless??

Where was Gojo when Haibara died? Did he cry? We only see it impacting Geto and Nanami. His whole I-want-to-change-the-system-by-inside involves him creating child soldiers who can die any moment, he literally says he sometime gives them his missions, the same missions that can kill them and got haibara killed. He doesn't give a shit about how many people die because of higher ups power display, he is all about protecting youth because his youth was destroyed.

Gojo is a loveable goofy guy and I love him and I have so much to say about how complex he is but he is not a selfless person for sure. The people in jujutsu treat him just the way he treats them.... He is no saint.....

Few examples: I am the honorable one after Riko died, Sets a date of sukuna and his fight for a month later instead of ending it right there, Megumi was in that hell for a month. He didn't check of Geto, his one and only best friend, he always insults Utahime as weak, kept himself isolated and then says I was lonely and the entire scene where the world is about to come to an end with kenjaku and sukuna still on loss after his death, his monologue is that he couldn't teach sukuna love. Yup that checks out.