We don't need to get to poverty levels to be carbon neutral. But we need to stop consuming for consumption's sake, and reduce some important bad habits. The structure of pricing must also change. People don't feel poor for not being able to eat caviar daily today, they don't have to feel poor for not affording beef daily tomorrow either.
But even if it can be implemented, it's a pretty bleak future.
And I have very serious doubt that the whole world can unite behind such selfless sacrifice. The free rider problem is obviously gigantic.
So I'd keep looking many other solutions.