I agree with your line of thinking. Ground invasion from outside probably wont happen and if it does it is going to be a massacre of the invaders. Even with the old commanders gone there are too many Iranians ready to fight back.

Iran's martyred leaders have explained the Mosaic Defense structure they have established. The resistance in Gaza, Ansarallah, and Hezbollah have show how this structure works in practice. Iran and the others in the Axis of Resistance built this systems together. Any person in the military who hasn't figured this out is not paying attention. The level of incompetence required to be this ignorant means they would fail even if they had 10x the resources the will have.

None of the collaborationist militias in the region are that stupid. If they were they would have been eliminated years ago.