Yes, I agree but water falling from the skies usually goes to rivers and dams where it can be used for irrigation. Like I said, technology can solve this problem by working on the demand side (being more efficient) and on the supply side ( by producing and storing water more efficiently). If we can live in Mars surely we can live on earth even with more challenging conditions.
But this is no excuse to keep warming the planet. We should be responsible and slow down global warming as much as possible and this again can be achieve through technology — solar energy, electric vehicles, etc.
Producing food is technology, if the systems we’ve built are obsolete, we’ll have to find new systems, that’s all.