Thinking about it from a first principles pov, the regime lost many of its key people, officers, and a lot of infrastructure and resources.
This 100% had some effect on its ability to function. The question is what effect.
Since it is a religious ideological movement, it has very strong cohesion, so its not going to break apart, demoralize or change its core principles.
It will also maintain the support of the highly religious Shias, however,while millions, they are a minority in Iran.
What its probably going to lose is its logistical capabilities, and its ability to exercise power and to make decisions in the periphery.
So it might still hold Tehran and places where it is strong, but Iran is a huge country, with an enormous population and mountainous geography. Places farther from the center might slip out of the regime's control. And it will need to work much harder to maintain the same level of control that it had before the war in Tehran and large cities.
This means that when the dust settles it will be either challenged by oppositional forces, or be forced to make concessions to gain back authority.
If it will try to massacre itself back to power, there will be a civil war.
