@ChocoBar9
When they show Shiggy screaming at everyone that he thinks heroes are actually bad and then explain, through flashbacks, that he thinks that because no heroes saved him and his grandma tried to protect him by abandoning her family, that is his
justification for his beliefs. It's why he wants to destroy everything, end the hero-oriented society, and kill all the heroes. We're being shown this so we understand Shiggy's point of view... and it's contrived. A hero-driven society where Heroes are constantly being called on to save people and help them, to the point that they are competing for fame and popularity and honing their skills to extreme levels so they can save as many people as possible, and no one in this entire city said "hey, there's this starving kid two blocks down, maybe someone should help him?"
The so-called "Bystander Effect" is also a greatly exaggerated and demonstrably false concept. The Kitty Genovese case, which is where the term was coined, had numerous people actually calling the police and trying to help, repeatedly. This idea that everyone sees another person suffering or in trouble and they just say "someone else will deal with it" is wrong and false. It makes Shigaraki's story come off as weak bullshit because it means that hundreds, even thousands of people saw him suffering and walked away for days, weeks, even months. That's statistically improbable, at minimum.