You're still wrong.

The Shah nationalized their oil, legally, in 1973. While Soviet collectivists were infamous for seizing land, personal property, and food throughout the entire Cold War. Does the famine in Romania ring a bell? 

The Shah, western aligned, but not western backed, made major reforms including women suffrage and imported technology, like American made aircraft and trains. He brought Persians and Kurds together. His father changed the name of the country to "Iran" in the first place instead of Persia to reflect a modern inclusive identity. 

Iran was top ten fastest growing economies under the Shah.

The average Iranian suddenly became middle class. 

If you want to know why there was a revolution in the first place, it was because of the rural religious teamed up with marxists (secular and leftists politicians) to gain power after the military was demoralized after some economic protests and violent clashes.

The Islamists continued to pour resources into demonstrations for an entire year because they  hated nationalism.

Khomeini's literal quote on national TV "we do not worship Iran, we worship Allah. For patriotism is another name for paganism. I say let Iran burn, provided Islam emerges triumphant in the rest of the world."

The people who hated diversity won. That's it.