The internal conflict over corruption, water issues and handling of the protesters had a decent chance to cause meaningful changes in government. Starting a war and attacking their civilians put those chances to bed.

Exactly. And this also want' just a protest. They were protest in the big cities and uprising from suppressed minoritiesm which explain the death toll among people from the regime.

Iran might have at best have a self-regime change, at worst split in 3. Now that the war is on, the regime consolidated.