There are innumerable forms of economic collapse. And there are counter-cyclical investments and businesses. During the Greek civil war there was, I recall, a fellow who had horded wheat before the collapse and sold bread for exorbitant prices during the collapse when people were starving. I believe he was later executed or punished in some way.Bear markets have people that profit from them and even win ‘bets’ on the collapse of the economy.
Short selling has made fortunes for good guessers. Even inflation can drive up real estate values- though one should keep in mind that real estate as capital is very small today in comparison to manufacturing and financial capital.On a micro-economic basis I would think that bootstrapping production for-oneself might be useful as a safeguard against starvation. One might grow plants at home for food and the market, produce solar and wind power and find other simple items to manufacture that are necessary.