The article and the thread leading comment are both nonsense in many ways, because you only have to look at the Comics Code[0] to determine what made comic books and superhero stories "for kids". They were sanitized to the point where they weren't telling "adult" stories and were stripped of many interesting possibilities.

Over time, the code lost its value and as of ten years ago, no comic company is following it anymore. Good riddance.

[0] https://en.wikipedia.org/wiki/Comics_Code_Authority