Adults liking kids cartoons are fine.(Tom and Jerry for exemple)Adult sexual interests are fine. Attaching them to child coded aesthetics is not.

Adults can like what they like. The issue is when those interests get projected onto material made for kids or built around childhood signals like bright colors, diapers, cartoon animals, preschool-style characters. People in those spaces often call every bad case an "isolated incident," even though the same pattern keeps showing up in the same fandoms. Adult media fandoms (Breaking Bad, etc.) rarely produce this problem because the source material is already adult. The friction appears when the source is child-oriented and adults treat it as a sexual canvas while saying "no kids allowed."
The internet is a public space. Posting sexual content that uses child-coded visuals in places kids can easily reach is not the same as keeping it private. Claiming "it's not my responsibility to protect other people's kids" while putting that material online is inconsistent.

"Adults have sexual drives; restricting them is prudish."

Sexual drives are fine; linking them to child aesthetics and kid-show imagery is the actual problem.


"No kids allowed" spaces and personal responsibility mean outsiders shouldn't police the hobby.

The internet is public, not a private club. Child-coded sexual content posted there is reachable by kids.

"Criticizing the pattern is just aesthetic distaste for odd people / "the culture."

Adult fandoms of adult media don't produce the same pattern at the same rate.

"Bad cases are isolated and don't represent the whole group."

Repeated "isolated incidents" inside the same aesthetics stop looking isolated.