I am shocked by the overwhelming negative comments

I do not think the author is arguing for mindlessly expanding the population disregarding our current consequences. I think his concern is that people seem to have forgotten that population growth is generally very good in most situations, especially in the long term. So instead of promoting de-growth as the solution to our problems, we should be trying to solve our current, and temporary, bad externalities of our growing population (climate change, loss of biodiversity), and that is a technological problem