How Can the Post Capitalist World Survive and Thrive on Our Ideas?

The question is, of what population can the post capitalist world sustain and thrive on with our idea and conos a billion like we currently have? Six billion, two billion less than a bility like, howmany people are you willing to lose to achieve sustain ability? Because i forgetno nomunity. And year optimistic, with proper technology and eco sustaine ability techniques, we can maintain a population close to what we have now. So it's not a so like it's approaching this uitanallegation issue. Yes, approaching this question in terms of like, how could the post capes world thrive on our ideas?