all that needs to happen is for countries to destroy their nuclear weapons

all that needs to happen is for governments to stop burning fossil fuels

all that needs to happen is for researchers to publish boring papers replicating others results

all that needs to happen is for fishermen to stop overfishing

Coordination problems seem easy but never really are. The chance of all the miners just suddenly agreeing to do something all at once is pretty low to impossible.

A million times this.

The point of a hypothetical suggestion is to direct a specific course of action. I am simultaneously amazed at how complex the 'hypothetical' construct is, and also how many people aren't able to reason around them... since this is basically what our big brains are for.

If you assume everybody involved just stops responding to their current incentives, you can solve any coordination problem, in a manner of speaking. But it's useless as a battle plan. Operationalizing a change demands that you pick a party you're talking to, and with full view of their capabilities and limitations, modify their current course of action in the smallest possible way that accomplishes a change.