Sure, they had a system of relatively successive monarchies, but that isn’t the same as having a single running system of government. And it certainly not somehow more legitimate than theocracy, if your own benchmark is democratic rule - which you just said was the determining factor of a government’s legitimacy.
Also, not for nothing, but the last monarchical dynasty was literally installed by the British, and propped up by Western powers until the people, or at least, a fanatically religious subset of the people, overthrew them.
Again, it’s not like I’m a fan of theocracies, but saying that their current government is illegitimate is absurd, whether viewed in the context of international relations, or internal support and control.
No one here is debating that there is some hidden upside to theocracy. They’re bad, we get it.
His point though, is that much like the Miami Cubans, the Iranian exiles that fled after the overthrow of the Shah, tend to be part of the old ruling class that had been disempowered. At least, the most vocal ones.
Also, just like Batista, Mohammad Reza Pahlavi, was enabled and backed by Western powers, before revolutionaries overthrew him and ended his dynasty.