No one is saying the idea is unrealistic. The discussion was invited to people by OP and we are all giving our thoughts on what this could look like and what this could look like if done poorly.
Also I hate to be “that guy”, but an autistic character isn’t creative nor is suggesting one amazing or brave or -insert overused positive adjective here-. I am all for inclusion and having more representation in media of all forms for special needs and other minorities, but I am not in favor of inclusion for the sake of inclusion. A character simply has to be a good character and what umbrellas they fall under should be an after thought.
A good character has dreams, flaws, purpose, emotion and above all else has to be believable. If you create a character with the mindset of, “Okay let’s make a character that has autism” that character will be inherently poor versus the mindset of character creation such as, “Okay let’s make a character who has a dream, who wants to accomplish something, who has friends to support them, who has shortcomings, etc.” Then through minor actions or speech patterns or the lack thereof hint at them having such disability. The character can admit to having it but not from minute one.
This is all coming from someone who is disabled, who has had developmental disorders and who has been wanted to be seen as Rothan the person not Rothan who is disabled. So perhaps there are my own biases at play but I don’t believe that to invalidate my points said here and above.