This should be a matter of course in general interaction with one another, as long as one is not physically impaired. Just as one does not stop in the middle of the aisle in the supermarket or block it with a shopping cart. People are becoming increasingly inconsiderate.
First of all, there are good reasons to trust trained professionals and a diagnosis over anybody else.
On topic: I’m diagnosed with ADHD and have not much issues with eye contact. It’s usually a conscious behavior for me.* I do a bit of eye contact and look away again, mostly with people I just got to know or when talking to people without an interesting topic. I do this delicate, but very conscious ‘yes-I-make-eye-contact-bot-not-too-much-so-you-see-I’m-interested-but-not-a-creep’ thing.
On the other hand I stare into people’s eyes when in a discussion I’m interested in and/or they have something interesting to say.
*I will be checked for ASD later this year.
No wonder most of of what’s being released is utter garbage by people with no life experience and anything to say.