I am in agreement with this position. Fortunately, for humans, it seems a higher quality of life leads to negative population growth (hopefully it happens fast enough).

If everyone wants to live and consume like a 21st century American, we need to make sure the world only has around 2 billion people (this is based on a fact I read that we need the resources of 4 Earths to sustain American style consumerism globally).

As our quality of life goes up more, the number of humans Earth can support gets smaller. Depending on the target global average lifestyle, we probably already have too many people by a significant amount.