any common prejudices that any average person could have?
I remember somebody who wasn't diagnosed as autistic until adulthood, and recalling the bullies at school, said that now those bullies declare that they never had anything against physically or mentally disabled people…and that might even be true. But, wow, did those schoolyard bullies hate weirdness.
There's also somebody who pretends to be allergic to peanuts only because nobody believes her when she says that she doesn't like peanut butter (but she loves peanut m&m's). So if somebody doesn't like eggs or something, a bad host at a party will insist that they've never tried these deviled eggs…and then cue being pressured to take a bite only to involuntarily vomit on the obnoxious host's shoes… Yeah it actually would have been better to lie and say, "I'm allergic to eggs," because apparently most people don't respect somebody's personal life experiences about their own dietary preferences.
There are also class markers. People appreciate "generosity" if the value being given satisfies them…but rarely think about if somebody's being so generous because they can afford to be generous. Like, maybe there's somebody out there with a generous spirit who shows by giving, but gets shunned because what they offer "looks cheap" or is offensive to gift any middle class person who is used to a higher standard of living. But nobody would outright say they hate poor people, because the image of "hating poor people" is probably something like hunting homeless people down to harvest their ears and wear those ears as a necklace (or something).
It's not considered "hating poor people" to pass them over for employment because their clothes were a shabby fit and slightly moth-eaten…because they couldn't afford any better clothes…which was why they showed up for a job interview…but, it is kind of hatred.
There's concern-trolling ("you're too promiscuous and I Worry About You" after going on three dates in two years, before 2020), anybody occupying a liminality between the hegemony and the least acceptable image of the opposite-of-hegemony ("passing privileges"), and contradictory feedback like people punishing you for being honest after constantly complaining that you're fake.
There's plenty of other small things: subculture, music genre preferences, celebrity admiration, academic or career accomplishments, accents (whether having a native language other than English, or being hard-of-hearing since birth, or having grown up in New Zealand before moving to the States), fandom ships (whewww some shipper wars can get vicious), if somebody cusses, smokes, drinks alcohol, if somebody is a "cat person or a dog person" or dislikes animals at all or would try to pet a bear because they love all animals equally even if it kills them, if somebody is open about their religion, if somebody has an extended family or single parent or stepparents or siblings or no siblings or a twin sibling—those all carry stereotypes.