Just knew what ableism is, but I don't think that is one but the more classic things bullies trying to downplay others by calling other idiots or autistic.

Either way, ableism or simply abusive behavior, both lacks respect, honestly and responsibility, which is a sign of immature behavior. Mature people can be playful, but they know when to act in the correct time, and definitely not in something that lead to a huge PR disaster.

Thus, being immature is the root cause of all these bad behaviors, including discrimination.