It's sort of a self reinforcing problem though - a lot of studies trying to understand biochemical mechanisms are taking our existing subpar labels at face valu

It's sort of a self reinforcing problem though - a lot of studies trying to understand biochemical mechanisms are taking our existing subpar labels at face value. They generally don't have the sample size to get remotely close to detection of the probably double digit distinct disorders that are making up the "Autism" group. And that is further complicated by natural heterogeneity found even in control groups. Personally I think coming up with better behavioral characterizations will be an important intermediate step to identifying bio mechanisms, because it leads to much more tractable lines of questioning. For example, we could be quantifying symptoms like rigidity and repetitiveness of movement, sleep quality, sensitivity in different sensory domains, etc. - which should be increasingly feasible to do at scale these days.