Blech. Feeding problems at birth for several weeks, refusing to feed if being touched (which a developmental pediatrician said was common in children later diagnosed with autism). Months old, if anyone tried to interact, turn face away. Very rarely make baby noises and very few letter sounds. Human touch leads to screaming. Seams in clothes causes screaming. Certain sounds, same. Toddler, never responds to name. Can't turn anything into a toy, it's just all lined up the exact same way every time, screaming if it's disrupted. Potty trained at five, saying one or two words a day at five. Sign language and augmentative devices an utter fail because the speech problems are tied to socialization, not a desire to communicate without the ability.
I'd love to know when they diverged from normal and how all that and more is just being different, not impaired. I dont get how people with autism can look at their past, how they can look at how very much they were locked in their own world to the point they couldn't feed themselves or go to the bathroom in the toilet rather than their pants, how they couldn't use the words to ask for help, and say that was an acceptable alternative way to live. How clothes, carpets, peanut butter, and birds singing was so much pain they'd scream out was a decent way to feel the world around them.
Even as adults there's significant impairment, even if it's not easily seen. Just because there's an adult ability to reason and mask doesn't mean there's no impact to daily life, and it doesn't start off in life as mild, there's a really deep well to climb up to get to it's not obvious.
I dont see how anyone could claim all that as different, or diverged from normal in utero.