[yummyfajitas]

If it were a completely rational "here's what happened last time", they would extrapolate "last time", compare it to the current situation extended for 50 years, and see which is worse.

I've never spoken with a single Iranian who actually did that. It's all just talk of vague negative childhood memories.

[jbooth]

Well, I'm just spitballing here, you probably know more Iranians than I do, but there might be something to the immediacy factor. Another revolution probably holds more immediate danger for their family than the current situation extended for 50 years, which is just another 50 years of relatively low risk. It's hard to take the long-term average outcome viewpoint when you're talking about family members' lives, and there's no guarantee a replacement government would be substantially better (the mullahs were talking about freedom from the shah when they started off).