Yes I think they were on some kind of mission to prove that Iran wasn't the Oppressive Regime portrayed by the press and everyone is loving and kind which of course not everyone is
I think both of those things are true. The regime is undeniably oppressive and fundamentalist, there are countless examples of this. It also flouts international law and has no qualms about detaining (and worse) people it knows to be innocent.
It’s also true that Persian people are hospitable, welcoming and open-hearted, which was ostensibly why this couple’s so-called risk assessment determined they would be fine. There is a sort of “liberal elite” (awful phrase) in Iran comprising (generally) educated urbanites who have been exposed to the world outside of an Islamic theocracy, and are appalled by their unelected leaders. Obviously, most of the diaspora come from this group and they have (also generally) flourished in the countries they fled to post-79.
However, the uprising against the Shah did not happen in a vacuum (and tbf he was no less corrupt than the current lot). The Islamists came to power as the result of a huge protest by ordinary people, there are remote villages where life hasn’t changed much in centuries and Islamic rule retains popular support in many places - Iran itself being a rather massive and diverse place!