People make judgements based on their assessment of the situation. Those assessments might be perverted by stereotypes, but usually only if they don't have any other experience to draw from. Stereotypes come into existence because the actual data isn't flat, and stereotypes directionally represent that abnormality.

Stereotypes only hold sway when people have no real-world experience. Israelis think Palestinians are "human animals", terrrorists every last one, because they haven't met any Palestinians (the ones in Israel they simply don't put into the same bucket). But once people meet a few Palestinians they see that this is wrong, that Palestinians are actually remarkably similar to Jewish Israelis. The problem here is the lack of experience, and the society selecting certain kinds of speech as acceptable and others as not acceptable (anything pro Palestinian is not acceptable, so their viewpoint of them can only go down).

It is these societal stigmas about what is permissible to say that are the worse problem than the stereotypes.

My comment was inspired by the Babylon Bee making a joke that Trump was going to hire Vivik Ramaswamy to run the White House 7-11.  People took offense, but Vivek didn't take offense, he thought it was funny.  I laughted  too.  My best friend in High School was from India and his family owned the local gas station. And I'll bet he'd laugh too. A lot of Indians came to America and ran 7-11s or gas stations because it was an easy way to get citizenship and make more money than they can make at home.  That was just a widespread thing when I was growing up, and maybe still now (I don't know).  But the punchline of the stereotype is that ALL people from India are interested in running convenience stores in America. It's funny because it is obviously not true, especially of Vivek (if you know anything about who he is). And even funnier because it paints Trump as a racist, which also isn't true but it's what the left tried to sell us.

Deciding not to help a black person because you are afraid of blacks... well, that's unfortunate. Nothing funny about that. Maybe she should get to know more black people. Depending on which black people she gets to know... she may well become even more afraid!  Hell, if she got to know my cousins on my dad's side she may even become afraid of white people.