And another one (that captures the dynamics of Braess) is "undercharging for fish makes fish harder to obtain" (because it causes existing suppliers and sources to run out sooner).

That's analogous because, in a Braess situation, the new route appears more attractive to drivers individually (just as underpriced fish does), but their usage of said route will disproportionately exhaust the network's capacity.

And in both cases, there's a kind of "tragedy of the commons" dynamic.