Solid Snake has certain qualities that could be described as autistic, such as emotional distancing (as an Aspie, “other people just complicate my life. I don’t like to get involved” rings very true to me), but this is more likely due to his trauma than him being neuro-divergent. Otacon is the true autistic hero of Metal Gear.
https://www.reddit.com/r/metalgearsolid/comments/10jmfpk/snakes_autistic/