My favorite story about this is related to the Dyson Sphere where the concept was first imagined by the sci-fi author Olaf Stapledon in his science fiction novel Star Maker (1937), only later it was scientifically explored by Freeman Dyson (hence the name of the structure).
This is one among many stories where sci-fi influenced reality by inspiring capable minds of thinking something novel and transform our lives.
As it was very well point by others, the absurd nature of circumstances these novels often occur in the author automatically gains the freedom to explore things that aren't that far from our reality, but in the circumstance of the story is nothing so people just don't take it too seriously.
If you are a technologist you might be interested in some space opera (a sub-genre of sci-fi) or you might like some utopian story on how AI and humans struggle only to find the balance in the end. But if your mind is curious about some strange ideas like zombies, post-apocalyptic warfare, surveillance states controlling human kind, a human kind without families and many values turned upside down.. these are just a tiny set of example of what you can find in this genre.
I believe the job of a sci-fi author is to give depth to the most weird, dangerous, and desirable ideas. Most people don't have the imagination of an author or their team that could include scientists as well, so they extrapolate what people think 1000 fold and then twist it and mix it with drama and thriller and everything else is there to add.
mic drop
My story with sci-fi started with me as a little boy dreaming to build an Evangelion-like robot, and from there onwards I never stopped. I play games, read books, dabble a little into writing as well, watch everything sci-fi, and this makes me a happier and better person. Or that's what I like to believe at least.
The science part
The fiction part
And then the science-fiction