If we manage to phase out meat consumption, and with it the need to raise farm animals, switching to a full plant-based diet, and improved public transportation

If we manage to phase out meat consumption, and with it the need to raise farm animals, switching to a full plant-based diet, and improved public transportation to the point car use become an exception, I bet the planet could hold twice the current population without significantly raising environmental impact. We waste a lot of resources feeding and sheltering cattle and automobiles instead of people.