If having 7 billion of us is destroying the planet and consuming almost all it's natural resources, do you all honestly think we can put another 4-5 billion here? Research from the UK and Canada at the UN showed that a infinitely sustainable population of 2B is about as much as the planet can handle. Even the 1 billion figure was questionable. (
here)
So, 10 billion will be the max, and then the planet will shake us off like a bad cold with climate change, rising water levels, lack of fresh water, disease, and running out of resources will kill us all off. Then after a few hundred million or a billion years, the remaining animals, insects, and bacteria, will reform a new equalized species regime on our planet...just sans humans.