I didn't make it through the whole video, I had to stop when the "doctor" started capitulating. In my experience people who hate self-diagnosis don't listen, period. They don't care about how much time and effort you've put into something, and this is an issue with society in general, people will automatically minimize the effort you've put into something if you don't have a degree in a relevant field. This is an even bigger deal when it comes to anything medical because for the average person doctors = unquestionable gods.
Those wackadoo folks want that to be real. No one wants autism. People find the descriptions of autism and then get happy that some things in their life start to make sense. Then they get sad because an autism diagnosis can harm your life.
Then of course if you DO have a degree in a relevant field, then they'll claim you are just some academic boffin with no idea how the "real world" works...