Because this is what it is going to take. Not even going underground en masse will work and that is essentially the most extreme social change I can see. (Even more extreme than space travel, cars, internet.)
Do you have a count of how many have gone extinct in the past decade?
> What makes you think humans are special?
Our brains. And yes, technology and science. Humans are extremely adaptable. Our ancestors survived an ice age with stone aged tech and spread around the world to live in all sorts of environments.
> Not even going underground en masse will work
LOL, what? Who is saying that the Earth will become so hot that we won't be able to survive on the surface? You think 3-4°C is going to have that effect?