Why are scifi authors so pessimistic about the future?

A common theme in many of today's scifi stories is one of desolation, typically a planet ruined by human activity, or a population which cannot be properly fed or sustained. Where is the creative thinking which gave birth to our precious genre? Where are the hero scientists who learn to feed a million people per square meter of farmland ? Where are the solar power plants which operate at 100% efficiency, or the nanotech waste recyclers which generate a nearly lossless society?

It appears most science fiction writers have been brainwashed by the "common wisdom" of today's society, they are no longer capable of imagining a greater good. Will there be any more big thinkers writing scifi for us all?

Perhaps I'm one of the last real science fiction writers, someone who imagines that today's "terrible" problems will be so easily solved that one day we will laugh at how serious we were. I can hear my grandchildren's voices echoing down from a distant future where they ask me in all seriousness "Grandpa, did people once really believe that Earth would get so warm the ice caps would melt? Didn't you have any scientists back then?"

The truth is that soon we will be able to feed 100 billion people without any significant change in the amount of farmland, we will have clean drinking water for them all from desalination and nanotech recycling, global warming will be a distant joke even if the sunspots do return. Resistant bacteria will be easily killed with phages, avian flu will be erased by targeted anti-viral agents, and cancer will be in the same category as today's tooth decay (which will have been eradicated). I see a day where rain forests can be created in a few years using ultra-fast growing bioengineered plants. Old growth forests will be established in time capsules orbiting the moon, then transplanted where ever we want to see one. Abortion will become transplant surgery where a 1-day old fetus can be safely transplanted into the womb of a woman who will love and care for her.

Are any big thinkers out there? Please contact me and we'll try to move science fiction to a more optimistic footing.