They got the autistic part right enough. Writing about a character with autism is difficult cause it isn't the most interesting thing. There isn't much to do with a character who needs to have a strict routine and gets easily overstimulated, not much room for growth, which is why authors tend to have the autism “fixed” midway through their work, which is just abhorrent, but it was done well enough. The book was a bit too smutty for a romcom (as the innocent book cover suggests) but they nailed the ending.