As I commented in another thread, there's no a priori reason to believe that the "average" glutamate receptor level is the "right" one. Isn't it possible that there are:

1. "Normal" people with a level of glutamate receptors at 10, say, on a scale I'm inventing for this example

2. "Autistic" (according to the DSM) people with a level of, say, 5, who are hindered by the effects of being at this level

3. "A little bit autistic" people at a level of, say, 8, who aren't hindered and don't meet the DSM criteria, but in fact actually benefit from the effects of being at this level

Some "normals" might then want to inhibit their glutamate receptors somewhat to get the benefits of being at an 8 or a 9 on my made-up scale.

Perhaps. But remember that this is a very complex 3D structure with varying receptor densities, it's not "The Glutamate Level", it's some neural network areas with higher or lower excitability connected to other neural networks.

Just like with ADHD it's likely that medication will at best have limited effectiveness and many side effects.

There are actually four types of autism, according to new research (and seemingly corroborated by my personal experience, though that's just an anecdote): https://www.medrxiv.org/content/10.1101/2024.08.15.24312078v...