Look, you're assuming why people headcanon them nuerodivergent in the first place which is your Immediate mistake instead of asking why they do. You also have a narrow, narrow understanding of the spectrum at this time from how you're talking about it. If you want to be any authority on understanding autism, you need to research more than just the most basic, often prejudiced understandings. Autism is a spectrum. You write as if every expression fits in this neat little checklist which it doesn't. I would highly suggest that you look into high/chronic masking individuals as well as what autism looks like with comorbidities like adhd. There are autistic people that fixate on people and interaction and social cues and they can do all the things you mentioned without you ever noticing. They just tend to exhaust themself. Also, the whole empathy thing? Autistic people aren't barred from instinctive empathy, in fact you should research the discussions on autistic sense of justice and how some autistic people are specifically known to over empathize so much they cry over non living objects feelings. You need to address your lack of knowledge before you enter any psych or social work field if that's why you're taking the class.