My child is on the autism spectrum, and they (preferred pronoun, but otherwise female (probably)) is occasionally, but not always, a picky eater. Certainly not as much as others have described in this thread. So obviously, with one example, I accept your hypothesis. They can sometimes be quite adventurous, and then go through long phases of great preference for one thing.
There are other aspects of their behavior, which may be autism related, or just child related, which are very easy to confuse with picky eating. For example, “I’m full,” “I don’t like this,” and “what is for dessert” are all synonyms. The literal meaning of any of those statements could be what is actually meant at any given time. This I think can be dealt with by parenting.
My kid went straight from a liquid diet to a chewable solid foods. They mostly refused to eat mashed up baby food, so we stopped offering it after about two weeks. I think the transition was around 9 months.
This so much. It makes it very difficult to plan ahead. Hot dogs were a winner for a long time, and then one day moved to the hated food list. Similar with chicken legs. Pizza went the other direction, and after being refused for years all of the sudden was a favorite (pepperoni, black olives, and pineapple).
So much this, also. All of the “consequence based” parenting techniques become worthless when your kid has an executive functioning deficiency, and doesn’t properly understand cause and effect. If you leave your gloves at school, then your hands will be cold the next morning, but a winter of cold hands does not create the organizational skills necessary to remember to bring them home.
Similarly, not eating what is being served leads to hunger, but only serving non-preferred food to a non-neurotypical child may be the equivalent of only serving piles of shit to a typical adult. No matter how much shit you pile in front of me, and how much you yell at me about it, I’m not eating it.
Taste perception varies between people, and has a genetic component. To many people, cilantro tastes like soap. There’s a gene for that. Other people may be extremely sensitive to bitter tastes. “Picky” can be understandable when all Tex-Mex food tastes like the sauce is made out of Dial bars.