Seek a second opinion. It seems to me that difficulty with self advocacy and passivity are one in the same. Difficulty with self advocacy is nearly a hallmark of autism.

This psychiatrist doesn't seem to know the phrase "if you've met one person with autism, you've met *one* person with autism." A single behavior or lack of behavior shouldn't dictate a diagnosis, and every person is different, has different sensitivities, different reactions. I'd look for another dianostic specialist! Maybe he was just trying to make you feel better, but "feeling better" doesn't get you the services you need! I'm sorry you got this reaction from the Dr. I'll bet you're frustrated.

Just because your son seems to be passive, doesn't mean that your son doesn't have autism.
The psychiatrist isn't taking into account several factors, a big one being that autism is a spectrum disorder. Not everyone with autism will respond in the same way in different situations.
Another really important one, is that with autism, the individual doesn't always know how to respond to an event, so can seem passive, when really they aren't sure what to do.
Please seek out a pediatric autism specialist who is knowledgeable with autism and can give a proper screening for diagnosis.

It’s just so frustrating I feel as though I have been waiting forever for a diagnosis and we are being turned down for one trivial thing. My son has had no support at all, other then the odd speech therapy session. He completely broke down at the start of school this year and has stopped communicating to anyone he just talks to himself all day! Iv had to start home educating him as the lack of support was heart breaking I’m really upset it’s taking this turn. He has suffered so much already. He has a lot of typically autistic behaviours no eye contact. Echolalia, not responding to his name etc no one is taking it seriously. Feeling really disheartened.

Reply this is the camhs psychiatrist who we’ve been waiting 4 years for! He said the fact he is passive with toys and can empathise with me, means he doesn’t have autism