One little problem is that the water from the poo & piss will always be less than the water that the poor people take in. So they'll still need to drink some bad water.
The actual climate models never predicted such a great heat increase as to kill most humans. Only enough to melt some polar ice so some countries will lose territory to sea, and raise the temperature a bit.
This is a piece of misinformation. The chip process speed progress is nearly over. There is no-way to go lower than 14nm, so only 2 "process shrinks" to go.