Given the activation of the “snapback mechanism” and a very large economic collapse is said to be about to occur in Iran, what would be the consequences for the regime?

One thing is clear. If you look at the span of these past 47 years, all the analyses of the Iranian Resistance about the regime and its policies have proven correct.
This Resistance said, “A viper does not give birth to a dove.” Massoud Rajavi repeatedly declared that this regime is incapable of reform; the moment it takes even a single step back, it collapses right there.
This regime will never abandon its methods because it knows perfectly well that what will ultimately destroy it is the people’s uprising, the network of Resistance Units, and the organized Resistance.
Wars and foreign interventions will not overthrow this regime. This regime has learned from the Shah’s downfall: the day it halts executions, torture, and repression, it will collapse instantly. That is why it will never stop.
Even economic pressure will not bring it down because in critical circumstances, it escalates executions and repression. Therefore, the only path to this regime’s overthrow is by the people of Iran and their organized Resistance.