I don't know the terminology around the world, but I do know that without a PhD, which encompasses more than just study (you need to do research and publish in reputable journals in your field), you cannot be called a Doctor.

People might refer to many others as doctors, despite them not having a PhD. I don't mind that, except in such cases where authority is assumed despite there being proof of such authority (anyone can get a Master's degree, even in evening classes or via correspondence, that doesn't give them authority in a subject).

As for Attwood, I would not trust him to work in the interests of autistic people as long as he still uses "disorder" and "Asperger's" in his bio. I'd rather trust an actually autistic psychologist who is up to date with what's happening in the world. There are many out there, many probably don't know that they are autistic and many are in training.