I live in Western Australia. Does that count as an "exotic" part of the world? Maybe not. My home country would probably be considered as "exotic".
I think I saw namaste's post today. She is from India. Also I sometimes (not too recently) see a Taiwanese person. I've seen Turkish and Israeli people, too. There don't seem to be any regular African posters except South Africans. I get the feeling that about 80% or more of the regular members are from the USA, Canada, UK, Australia, NZ and South Africa. Most of the rest are Europeans. Then a few Asians and Latin Americans.
I think it's to do with the fact that this is an English-speaking forum and that maybe in Asia, Africa and Latin America the awareness of autism is very low. Just my guess.