Standards for what is socially considered appropriate for children has changed over time, at least in American society. For example, in one of the DVD re-releases of the late 1960s-early 1970s seasons of Sesame Street, a children's television program that airs on PBS, there is a disclaimer that says that these re-released episodes are intended for adults and not for children due to the changed social norms. And these changes have nothing to do with racism or cartoon violence; these changes have to do with other norms such as children talking to strangers.

This YouTube video has a segment of an interview that discusses this further:

https://www.youtube.com/watch?v=5Vow6p7uKVw