I haven't seen the author you criticize ever promoted either that or that he suggests that humanity as the whole should revert to "hunter-gatherer primitivism."

I see now you are summarizing his writing just as "just lots of pessimism". But the numbers don't lie. Unless you directly depend some specific miracle (and you should state which that is supposed to be) the numbers, if extrapolated assuming continuous growth, result in resource exhaustion. Continuous growth is provably impossible without some miracle involved.

And I guess the above observation you translate to "the whole thing is just impossible"? Would you define your "whole thing" as the "infinite growth and scientists will give us a miracle allowing that"? If not, what are you talking about then?

In the words of Tom Murphy, from the article:

"The physical reality is that we are living in an ecologically, evolutionarily untested paradigm that is very recent (on relevant timescales) and powered by patently unsustainable practices and resource use. The cost is rapid ecological degradation and global disruption to the biosphere. It seems quite clear that the track we are on does not lead to the stars, but to ignominious self-termination of this whacky mode called modernity."