the entire discussion of "causes of autism" has a crux, autism isn't a specific thing. it's a current catchall term that we use for "brain performing differently", not even "sub optimally" as some people with autism have enhanced performance of brain functions. imagine thinking that someone who lacks social skills but has a 200 IQ has the same disorder as someone who is a completely nonverbal adult who needs 24-7 care for their entire life. this is one of the frustrating things about the removal of Asperger's syndrome from the lexicon. it was a clear distinction within the autism umbrella for generally high functioning, by contrast, individuals who had a more specific set of symptoms and characteristics. now we're instead of specifying and creating more targeted approaches to care expanding the umbrella and including the lightest side of the spectrum to try and push a sense of inclusion. it's the "it's ok to be racist, we're all racist" approach to something that has a medical outcome.
i envision a time in the future where "autism" is nothing but a relic linguistically, and we have given up on the overarching spectrum diagnosis theory to create more distinct categorical types of disorders that have more clear cut causes and better therapeutic treatments and strategies for coping. this is the lived reality of most special educations professionals already, there is no one size fits all approach to educating autistic children. they must create personalized curriculum for each individual, and in doing so are laying the ground work for the eventual shift that must come. even if we find separate disorders have the same causal links and chalk differences up to the complex developing human brain we must accept a large range of outcomes demands eventual categorization and more specified approaches to treatment. rather than living in a world where autistic children of wildly different circumstances have their development left up to the roll of the dice that is their eventual care team's skills, or lack thereof.