The term 'politically correct' has become synonymous in some circles with being overly sensitive.
Whether you see political correctness as polite, necessary, or outrageous, most of us can agree that there is definitely such a thing as taking a joke about a sensitive issue way too far.
I find that there tends to be a bit of a hypocrisy with bigoted people. Like sure, no problem with making fun of the systematic imprisonment and mistreatment of immigrant children, but make Princess Ariel black? Unacceptable.