I do not mind constructive criticism; it helps oneself to improve. However, I am afraid I have to disagree with @KoochehChannel YouTube blogger for accusing Mohammad Reza Shah Pahlavi of causing the 1979 Revolution in Iran due to his modernization policy of Iran.
مقاومت دلیرانه دختران شایسته ایران در مقابل دیکتاتور دیوانه در زادروز محمدرضاشاه پهلوی!!! - YouTube
Mohammad Reza Shah Pahlavi I succeeded his father, Reza Shah the Great, as the King of Iran. Reza Shah the Great inherited Iran from the Qajar Dynasty, which ruled from 1789 to 1925. Unfortunately, during the Qajar Dynasty, Iran's fortunes began to decline due to poor management of both domestic and foreign policies by the ruling elites.
To name a few, the Qajar Dynasty poorly managed their statecraft, Iranians did not have access to clean water, and Iranians suffered from environmental issues which affected their health—foreign powers like England and Russia plundered Iran's wealth.
One vital point to remember is that a New World Order was emerging in the region during the time of Mustafa Kemal Atatürk, the founder of the Republic of Turkey. Atatürk modernized the country by moving it away from religious values and towards European values. He changed Turkish letters from Arabic to European-style letters and implemented other measures to reflect European style and culture.
Reza Shah the Great was moving Iran toward modern Iran and not a European way of life. Reza Shah the Great never changed Persian letters to preserve Iran's cultural heritage. The King was a strong supporter of social justice. However, England, Russia and the US curbed the King's plan for the modernization of Iran during World War Two. They attacked Iran and caused Reza Shah the Great to abdicate the throne in favour of his son Mohammad Reza Pahlavi I to ascend to the Peacock Throne.
Mohammad Reza Shah Pahlavi I's first wife, Fawzia of Egypt, could not stay in Iran because Iran did not develop like Egypt.
As a result, Iran was way behind the times, and Iranians lived in poor conditions. Even in today's time, Iran's infrastructure is going to be the time when the Pahlavi Dynasty built Iran's infrastructure. The Islamic Republic of Iran's actors are wasting Iran's resources and causing environmental degradation with their mindless policies and misallocating of precious resources.
Coming to the focal point, why Iranians went against Mohammad Reza Shah Pahlavi I? Political philosopher Machiavelli suggests that people revolt against their masters if they realize that they can improve their situation. Iranians followed this principle when they rebelled against Mohammad Reza Shah Pahlavi I.
The Western countries wanted to avoid the Middle East becoming economically prosperous, as it would have threatened their economies. During the reign of Mohammad Reza Shah Pahlavi I, Iran made remarkable economic progress, which alarmed the Western nations. In response, the Western media began to spread negative propaganda about the Pahlavi Dynasty, accusing the King of embezzlement and human rights violations. Khomeini, whom the West supported, gained popularity among Iranians because they believed he was a descendant of Mohammad and wouldn't lie. Khomeini promised a free-ride society to Iranians by toppling the Pahlavi Dynasty as Iranians came out of their homes and caused unrest in Iran, and the King left Iran.
Machiavelli's theory suggests that people change their masters when they think they can improve their situation. This idea holds true across all cultures. In Ontario, Canada, Mike Harris of the Conservative Party won the election for Premier's Office by promising to boost the economy through cuts to social programs. The people of Ontario voted him into power, and he formed a majority government and started slashing social programs. However, this did not result in economic prosperity for the people. Instead, they experienced poverty, while Harris's friends were appointed to Crown Corporations and given other high-paying jobs. Despite this, in the following election, Harris offered voters $50.00, and they re-elected him with an iron fist to rule Ontario.
Justin Trudeau, the current Prime Minister of Canada, is aware that he may not be able to form another government and, therefore, is proposing a Basic Universal Income to gain public support and secure votes during the upcoming election.
Mohammad Reza Shah Pahlavi I played a significant role in modernizing Iran and ensuring peace and security in the region during his reign. However, the Iranian people were responsible for their actions during the 1979 Revolution, as their primary motive was to improve their financial situation. Unfortunately, their participation in the revolution resulted in significant losses for Iran, as they became the biggest losers in the political game.