It's interesting to come across your post about this, because I have been aware of this issue lately myself, and was thinking about it just the other day.
I've noticed that I've gone on an arc of a journey with eye contact.
When I was a teenager I became actively aware of how painful eye contact was to me, figuratively speaking. I became acutely aware that I couldn't stand to meet someone's eyes.
I then consciously, over the years, made an effort to change that. I realized that things went better if you confidently look someone straight in the eye, and engage eye contact in an NT way (I didn't know it to be "an NT way" back then, but that's essentially what it is and was).
So then through my 30s and 40s I believe I was a lot better at "normal" eye contact -- although having said that, I could be wrong. Maybe that was my perception within myself, but the reality to another person was that there was something still "wrong" with my eye contact. I don't know. I just know I personally believed I was now "good at it."
So the most recent part of the journey -- I think I've now once again become worse at it!! !
I've recently, actively caught myself not making the kind of eye contact I had previously learned is the amount and manner that the rest of the world mostly makes. I have some self-awareness enough to know that I've failed to "keep up the act" -- and I do feel like most of my life I've felt a pressure to not be myself because myself was "off" -- going by the reactions of other people, that is.
Now my eye contact is very poor, I've noticed. I catch myself diverting my eyes and suddenly realize, many times a day, that I diverted my eyes at a moment when an NT would have maintained contact, or even that I failed completely to make eye contact, in a way that I used to make sure I did.
I don't know whether it's a combination of feeling very, very stressed out, chronic sleep deprivation for a long time lately, or even that I got my diagnosis only months ago and perhaps I'm "growing into" accepting it. Does growing into accepting it mean that suddenly I'm allowing myself to act more spectrum-y than I used to? I don't know. It feels complicated for me. All I know is that my eye contact has become poorer and poorer lately.