Look at any financial institution, at any bank. They're all photocopies of each other. There's no diversity of institutions and even less diversity of currency. Therefore, just as you say its very logical that an ecosystem like this will collapse, it's very predictable a monetary system like this will collapse, too. And it hasn't finished collapsing, by the way.

Money is created through bank debt. When you go for a mortgage through a bank, they give you $100,000 to buy a house and basically send you out into the world to bring back $200,000 in the next twenty years. The first $100,000 is principal, and the second is interest.

The Future of Money: Creating New Wealth, Work, and a Wiser World

GREED AND COMPETITION ARE NOT THE RESULT OF IMMUTABLE HUMAN TEMPERMENT…GREED AND FEAR OF SCARCITY ARE IN FACT BEING CREATED AND AMPLIFIED …THE DIRECT CONSEQUENCE IS THAT WE HAVE TO FIGHT WITH EACH OTHER IN ORDER TO SURVIVE

Conventional money is supposed to be doing everything. By adding in complementary currencies, you actually get different types of things and different outcomes from different complementary currencies.

Our [American] money system is structurally brittle. It doesn't matter if you put a very clever guy or a stupid guy at the wheel. The clever guy will take a half hour to have an accident, and the stupid guy will take ten minutes.

Complementary currencies work in addition to existing money, rather than replacing existing, official money. There are whole different families of complementary currencies. One of them is local currencies. One is regional currencies. Another is functional currencies. Another is social-purpose currencies.