I don't think anyone questions that humans will survive. It's just unlikely that the complex global supply chain that gives us complex tools like microchips etc will survive. And may be massive famine etc after just a few harvest failure, or after the grain can't go down the rivers to the sea any more. Naturally not for the very rich, you can probably buy a bag of rice at a price. It's not survival that's at stake, its civilization and all that.