I like how this post fights with "scalar fallacy" (https://news.ycombinator.com/item?id=8132525, http://observationalepidemiology.blogspot.com/2011/01/scalar...), prevalent in popular psychology.
My small nitpicks:
1. IMHO, the gradient (from "a bit autistic" to "highly autistic") makes sense - as long as we treat it as the first principal component of a multidimensional process. I know many people who learned that they are autistic in their 30s, as on ALL axes, their symptoms were relatively mild (especially women, who are vastly underdiagnosed). After realizing they are autistic, they often cried, explaining decades of their life and why they always felt different.
2. While I understand where "Don't assume anything about an autistic person." comes from, I disagree. If we take it literally, the word "autistic" makes no sense (as it is not related to anything). Sure, stereotypes are both inaccurate and harmful + there is great neurodiversity among autistic people - "If you've met one individual with autism, you've met one individual with autism". The best antidote is Bayesian thinking - having reasonably wide priors and modifying the posterior with each measurement.