The first publishing of "Limits to Growth" suggested that if immediate actions were done to curtail growth and use of resources, the world could possibly in many decades peak and then come back down to a sustainable flat line. That was in 1970. 54 years ago we may have had a chance - although the research didn't include many things not known to them, including the impact of climate change that was already underway and just not obvious (the ocean was buffering much of the effects for a long time).
My non-scientific opinion is that crossing the line of hunter-gatherer to agriculture was the real point of no return. We gained a lot from that, but it also sealed our path and fate. Finding the rich energy source of petroleum was the final accelerant.