Tony was a victim of his upbringing and of society. But so were his mother and his sister. It comes down to which road a person chooses to take and what they decide to do with their lives when they are victims of society. Some people learn from their being victims of a bad upbringing or being a victim of society. They choose to not make the same mistakes that they saw others make in their upbringing and so they decide to strive for a legitimate and educated life. This is Mama and Gina.
Then there are those, like Tony, who become bitter from what they've experienced, bitter from being a victim of their society, and they choose, like Tony chose, a life of crime. They get this chip on their shoulder which makes them think that the world owes them everything and that they owe nothing to the world. They decide that working hard gets you no where so they just take what they want from hard working people and society itself. This was Tony. His making that choice to take what he wanted, kill people doing it, and not caring about the consequences or the lives that he was ruining by making money from the drug trade makes him evil. When a person does not care that his making money from the drug trade is ruining the lives of families and the futures of children, that person is both selfish and evil. Everyone has choices. It's what we do with those choices that defines what and who we are.