To my knowledge there really aren’t any downsides to a diagnosis, as a matter of fact you may even have new legal protections under the Americans with Disabilities Act, or ADA: https://autismsociety.org/wp-content/uploads/2021/11/ADA-Fact-Sheet-1-1.pdf
You also have a right to not disclose your diagnosis per HIPAA, so long as you wouldn’t need an accomodation.
Looks like a dope little device but at that price I think I might be more interested in a Steam Deck.