I know the news stories seem to debunk the fears, and the real life stories might not 100% reflect the science fiction but having fun anyway:
Black Mirror episode “Metal Head”: robot dogs attempt to exterminate the human species.
Snowpiercer the movie and TV series: Scientists release a substance into the atmosphere to block the suns rays to combat global warming; the plan backfires and the earth cools down to inhabitable low temperatures instead
Terminator movies: we know what goes wrong. And there’s plenty of AI stories out there.
Planet of the Apes: humans are overthrown and enslaved by apes.
I don’t know that the point of Snowpiercer is some sort of fable against geoengineering, but rather that geoengineering is a sort of MacGuffin to set the stage for all the antics on the train itself.
At any rate, we’re going to have to do something, and getting nations to agree on carbon emission restrictions is proving a lot harder than I would have expected. So I imagine geoengineering is where we’ll end up in the short to medium run. It might not be the very best idea, but it’s better than the alternative.
The father of the internet, Sir Tim Berners-Lee, credited Arthur C. Clarke’s short story, “Dial F for Frankenstein”, as an inspiration. Did he read that story all the way to the end or even look at the title?
I get that there are laudable reasons for pursuing such research, such as slowing/reversing aging, and curing genetic disorders like Down Syndrome. However, I find it more likely that if it is successful, a multi-billion dollar industry will spring up around it where the ultra-wealthy will pay top dollar to ensure their kids will grow up to have the body and looks of Jason Momoa, or be a natural stud at some sport, etc.
And I can also envision a dictator-type using this technology to produce a clone army, reminiscent of Star Wars, with soldiers having otherworldly strength, endurance, intelligence, and pain resistance.
He also wrote about atomic bombs in The World Set Free, which gave Leo Szilard inspiration for their potential and the idea of nuclear chain reactions(Wells wrote his story based on the ideas of Frederick Soddy, before the concept of a nuclear chain reaction existed)
Of course, he also wrote the first story about tanks for warfare (although his tanks didn’t use a caterpillar tread, but a much more complicated thing called the Pedrail Wheel).
He, too, wrote about an internet-like concept and a Wikipedia-like living “Permanent World Encyclopedia”
Scary guy, that H.G. Wells. Even without his Martians.
My contribution: Robert Sheckley wrote about the potential for trouble caused by autonomous artificially intelligent drones back in his 1950s story Watchbird, which started going after people as with the mechanical dogs in the Black Mirror episode. The story was very badly adapted as an episode of the short-lived Masters of Science Fiction TV series.
This is what I came to post, pretty much. If we do not take the soiling of our own nest seriously, and soon, we may not be around long enough to do any serious space travel. Also, that whole inbred violence and savagery thing we have going on - we need to solve that one as well if we hope to walk on other worlds.
But, space travel is sexy and exciting and several movie franchises as well as plenty of authors have made people believe it is inevitable within the next few years!
Elon Musk’s Mars colony is gonna be like Lord of the Flies…
As to the monkey-human embryo, thanks for reminding me of the nightmare I had last night about it. I dreamed of several of these, grown up, looked and acted mostly human. In fact, indistinguishable. Thanks, OP.