This is just math now, as the population reaches 10 billion, note sarcasm required or Disney rosy scenario. It being humans will have exceeded the carry capacity of the planet and the planet likely would have reached resource depletion. Finding extracting resources from asteroids far to complicated and dangerous. Also taking to long in transit time to be practical. Then the human race will do whole sale dying living on a hellscape.  Can we escape maybe but do we have the political will most definitely NOT.