So there are a bunch of different things in this post thay seem to need answers so Ill try my best to find resources for you.
First off, neuroprotection is defined as "the relative preservation of neuronal structure and/or function". So we have thousands if not millions of neurons in our body, and each neuron releases neurotransmitters such as endorphins, serotonin, dopamine etc. To be absorbed by other neurons which affect our mood and bodily functions.
Some fungi, such as Lions mane mushrooms have been shown to potentially aid in neuron growth and improve symptoms of alzheimers. In this way they can be neuroprotective.
Now, it has been found that autistic people experience synaptic pruning at a much, much lower rate than neurotypical people. Synapses are like little connectors that help neurons communicate with eachother. As infants we all experience synaptic overgrowth, then we experience synaptic pruning which gets rid of less efficient connections.
Knowing that, my brain goes to thinking that if anything Lions mane might reinforce some aspects of autism! That's just my first thought though and is probably inaccurate.
I don't know much about how adaptogens work, and I've never really considered a connection to autism before but I did a little digging but there seems to be no real research on this. From my limited understanding, adaptogens seem to work similar to how ingesting vitamins and minerals might work, or coffee or tea. They also cover a broad range of herbs and fungi and they all work differently.
Do you mind explaining how the cordyceps tea made you feel "less autistic"? So far there is no research indicating that there is or will be any "cure" for autism or way to "rewire your brain" to get rid of your autism. If anything, it is likely that adaptogens might help you feel calmer or more focused, where the stress or anxiety might be caused by overstimulation experienced due to autism. So like the overstimulation may remain but they may help to manage it more effectively. Does that make sense?