But AI will figure out a way for us to survive without food or water. Checkmate environmentalists!

I think both are making a valid point here. The first is making a point about understanding logistics and proportion of things and not falling prey to “big number = bad”, which could lead to anti-industrial thinking if taken to an extreme (not to be confused with anti-capitalist). The second is making a point about priorities; that some things are much more easily justified as consuming a lot of resources since they are so vital to staying alive and that if you have to choose, you should probably be choosing the necessity first.