Being bluntly honest. People who are neurodivergent can struggle with being "politely dishonest" and can tell you what they think in a very blunt manner without meaning to offend.

Not engaging in small talk. Again, people who are neurodivergent tend to prefer talking about things that fascinate them and can have a hard time understanding the point of talking about just whatever.

Struggling with being on time, struggling to focus on someone or something, struggling with eye contact. In general, neurodivergent traits tend to be seen as "asshole behavior" because they are abnormal and don't conform to society. People who aren't normal tend to be viewed as assholes because how dare they inconvenience me by being different.

Source: personal experience as well as listening to the experiences of others. I've been hit with all these things at least once and accused of being an asshole, aloof, and/or self-centered.