You asked the question: "Are these people really that ignorant,?" The answer is yes! I have been around for 80 years and travelled to over 40 countries and have met indigenous people in the jungles of new Guinea more intelligent than many Americans. What these people you mention are exhibiting is not "racism". It is bigotry and hatred. As every person on the planet is a Homo Sapien, therefore one race, "racism" is not a word.

https://medium.com/my-unpopular-opinion/racism-7f0d0d7d6754