@AutiMum
Was it a Psychologist, or an Educational Psychologist who did the assessment? There's a big difference in their roles and 'who diagnoses what'
For Children, Autism assessments were often carried out by a team and until this latest huge backlog, many still were.
The team consisted of Paed, Ed Psych, SaLT and OT. All of them interviewed the child in different settings, saw parental and schools input, then got together to review their observations and only then, if all agreed, a diagnosis of Autism would be given. The diagnostic reports were comprehensive.
Neither SaLT nor OT were able (qualified?) to diagnose autism but they could diagnose other conditions alone e.g. SaLT could diagnose Semantic Pragmatic Language Disorder and others, OT could diagnose Sensory Processing Disorder (in the time before it was incorporated into an autism diagnosis) and Dyspraxia among others.
Ed Psych was usually the one to diagnose dyslexia.
A Psychiatrist alone can diagnose ADHD etc. but that's because with that comes medication advice and prescription.
My DD is adult now, and adult diagnoses are carried out differently, so maybe things have changed.