It's not about the supply and demand. They mentioned in the article that the real price of bitcoin in iran is still close when compared to other countries. It only seem high at first because the rates are low for the exchanges but the truth is they're using a different rate and not the official one. The situation in Iran seems to be like that for quite some time as i've seen older discussions about having way different rates and now it's being brought up once again after what happened recently between them and the US.