Doesn't matter what or who is the regime.

Disagree. A theocracy is bad. Bad for its subjects, and bad for everyone else. If they could morph into a democracy, that would be so much better for everyone. I've read numerous articles that the Iranian people hate their government, but there really isn't an organized group to oppose it. And change is out of the question until something major happens.

Tribalism.

Debt.

Climate.

Divisions.

Sure. Don't know the Iranian debt situation, but the rest of that is true (and has been true) of every large collection of people (i.e. nations) since forever. Whether it's black and white, Hutu and Tutsis, segregationalists and integrationists, Baptists and Congregationalists (from whence Jefferson's famous letter arose), or whatever. People always form groups. The diabolical among them find ways to weaponize it, and then mayhem ensues (e.g. the NAZIs, FOX "News", religion -in general...numerous examples-, Hutus and Tutsis, European soccer clubs...just so many groups and divisions).