Some protestors are not the nation. Were the 1989 demonstrations in China representative of the will of the people? We know that they weren't, but if you only consume anti China media, you wouldn't know.
The protests in Iran have some legitimate concerns, which the government actually addressed already by abolishing the morality police (but remember, 40 years ago they were demonstrating for more religious rules in public life). But the ultimate reason we're seeing protests in many countries now is inflation and the cost of living crisis. We currently have major protests in Spain, Peru, Sudan and Jordan as well as Iran. Earlier this year there were major protests in Sri Lanka and Pakistan. People whose standard of living is going down are blaming their government. Iran being sanctioned and protests having a history of success (ie the revolution) makes protests more common