Effects above 2C will not, in fact, "Kill everyone." The idea that this whole thing is some binary condition between "Everything is fine" and "Everyone dies" is complete nonsense. Every fraction of a degree we reduce or prevent will make a difference to survivability and quality of life for people all across the planet.

It all matters (in the sense that every country, big and small, should be trying to decarbonise; obviously, those efforts should be targeted on billionaires and massive pollution driving industries where we'll make an actual difference, not completely ineffectual headline grabbed like plastic bags and drinking straws).