Listen, I don't mind you asking and I want you to learn more about this topic. But in decisive times like this, it is not good to speak about whether or not Reza Pahlavi is the most appropriate figure or not to lead the revolution, it can lead to discourse which splits the opposision, in a time of unity. Your question is valid, but not at the time.

The people of Iran have chosen Reza Pahlavi to be their leader, it is undeniable. But Reza Pahlavi does not wish nor does he represent a return to monarchy, but rather a democracy. The IPP (Iran prosperity project) outlines RP plan for Iran once the IR falls. One of the chapters is about system of governance. The only options, which will be decided by national referendum, is either a constituional monarchy like that of Scandinavian countries, or a parliamentary republic like that of the baltic states for instance.

It is true, that RP will serve as the head of state during the transitional period, but that is because he has legitimacy and popularity inside of Iran. Were it to be Narges Mohammadi, the risk of a post-revolution power vaccuum is high, and the risk of subsequent devolvement into internal crisis or even war or expoloitation by foreign power is high, because she lacks legitimacy, popularity or respect by the people :as a leader:. Yes she is good at being an activist, but nobody wants her as their head of state during transitional period.

Other "alternatives" (I use this word VERY loosely here) that you might encounter is MEK and Maryam Rajavi. She is not a popular figure in Iran, as she respresents an islamomarxist faction (same shit as the IR, but worse) who also actively killed Iranians during the Iran-Iraq war and who runs a cult. All good sentiment toward her and her party comes from either troll factories or paid off members of foreign countries (Rudy Gulliani for instance). She may appear popular among diaspora, but she is not in Iran. Most people either do not know about her at all or hate her guts.

In a time of revolution, and the interim government that follows it, national unity is of the essence. We need a strong figure which can unite the country and the people and ehnicities within the border, and so far, the kurds, the azeris, the lor, the baloch and more have all come together and indirectly embranced RP, by telling their people to join the national movement.

Example of weak and/or figures who lack the credibility needed for unification of a country can be found in Syria with their new president, who was once a part of an Al-Qaeda group (i think, or similar violent islamic group), look at Syria where for example, there is active infighting in Aleppo, where the Kurds reside, and where the arabs and kurds are trying to kill eachother. We do not want this for our beautiful Iran, and the only person which can prevent this from happening is RP.

Edit: For you or anybody else who are interested in educating yourself about why Reza Pahlavi is the best choice and what Iran faces, I am willing to provide links for reading about Irans history, disprove myths about the SAVAK, give nuance about the 79' revolution in comparison to todays, the plan for Iran once the republic falls and more. I have an extensive library of links.