I have a very sweet elderly friend of the family who only uses Facebook for church-related stuff, and since I'm "the tech guy" she asked me to look at her facebook and help her understand why she sees so much Trump, right-wing, hateful, violent, "Nazi-adjacent" (interestingly never -overtly- Nazi) stuff in her feed. I didn't have the heart to try to explain to her demographic bias, revealed preferences, and overlapping group interests, so I just said it's probably a software glitch in Facebook.