Degrowth is not a viable alternative on a world that's still has a large number of people that need better standards of living, and will still be adding a couple billion to the population. There's no viable economic or political model that would make degrowth work.
degrowth is the only thing that could work at all, the lack of compatible economic and political models that would be compatible with is exactly my point, which is why we will ultimately not solve the problem.