Even amongst people who are presumably, on the whole, intelligent, and by definition (due to the nature of the work that attracts people to HN) good at understanding complex systems, the amount of down-playing and hardheadedness and frankly closed-minded thinking -- all in the service of a kind of soft denial -- displayed throughout the comments here is astounding. And it seems to stem from either unwillingness or inability to truly see the magnitude of the problem, the system affected as a whole.
Climate change is not happening in a vacuum. You are completely underestimating the monumental effects of what you're conceding will happen (disproportionate harming of lower income equatorial countries), and overstating the consolation of there still being substantial areas of habitable climate.
We are poised to see the largest refugee crisis in history. The global supply chain will lose its most foundational workers, the destruction of its most foundational resources. Wealthier nations will not welcome those refugees with open arms, and we can all but expect their arrival to even further foment the rise of right-wing extremism, which will continue to contribute to instability in their own native countries.
Furthermore, those shrinking but still existent areas of habitable climate will encourage violence simply by way of everyone on the planet becoming more and more aware of how rare they are. And even that ignores the fact that "habitable" does not mean "untouched." Those places will have their own purely-climate-related problems, politics and violence aside.
And that is but one of dozens or even hundreds of equally massive, intertwined, complex issues resulting from climate change.
The very literal existence of humanity may not be doomed (though it very well may be), but any semblance of global order and a functioning society very much is.