I think people tend to underestimate human resilience. To use the bronze age collapses as an example, sure, it brought down existing polities, the names drawn on maps changed.
But most of the cities were still there. People still lived in them. Does changing the rulers while keeping a similar paradigm ultimately matter that much? I’m reminded of accounts of the experiences of some Afghanis during the American intervention there. First they paid their taxes to the Taliban, then the govt we set up, then the Taliban again. shrug.
While supply chains could be disrupted, any time that happens it opens the door for another profitable enterprise to rise in its place. People suffer, some die, but life goes on. If the knowledge of how to build those supply chains is still around, it will be done, and swiftly.