Who is saying she should be prevented from speaking?

Social responsibility is broader than legal responsibility. Trump's bleach comments were dumb, and if he were smart enough to understand how dumb they might be, also irresponsible; but they were not illegal. Part of responsibility is understanding that people are influenced by the attitudes and ideas that they come across. Maybe not very much, maybe not very many of them, but it can have an impact.

It might be annoying that when you're a public figure, you are a de facto role model. If you don't like the scrutiny, and increased pressure to express yourself in a pro-social way. But unlike monarchies, where the members have this thrust upon them, Joy chose this career herself.

So--prosecute Joy? Haha, no. Stop her from speaking? No, at least not unless you silence everyone who might have a contrary perspective to hers. Criticize her for perceived anti-social behavior? You bet! That's completely in bounds. Defend her behavior as reasonable? Sure, make the case!

But pretend that humans aren't influenced by what they see other humans doing and hear what other humans are saying?

Hahaha--oh--I think you've got the wrong species.