It seems surprising that so many collapse ideologies are focused on local production and self reliance. I would naively read environmental trends as tending to require more interdependence: we’re going to have significant population centers with no arable land and no fresh water. Maybe they’ll find ways to cooperate and trade for what they need. Maybe they’ll migrate en masse to better resourced areas. Maybe they’ll resort to war and plunder. But at any rate there is going to be an interaction.