My understanding is that an issue is local hyperconnectivity / long-range underintegration, linked by the E/I imbalance.[1][2]

[1] "The findings support the idea that an imbalance of excitatory and inhibitory signals in the brain could be contributing to traits associated with autism, the researchers say." https://medicine.yale.edu/news-article/molecular-difference-...

[2] "Converging evidence from diverse studies suggests that atypical brain connectivity in autism affects in distinct ways short- and long-range cortical pathways, disrupting neural communication and the balance of excitation and inhibition." https://doi.org/10.3389/fnhum.2013.00609