Change is the principal feature of our age and literature should explore how people deal with it. The best science fiction does that, head-on.
Predicting has a spotty record in science fiction. I've had some failures. On the other hand, I also predicted the fall of the Berlin Wall and the rise of fundamentalist Islam... and I'm not happy to be right in all of those cases.
There's no doubt that scientific training helps many authors to write better science fiction. And yet, several of the very best were English majors who could not parse a differential equation to save their lives.
But honestly, if you do a rigorous survey of my work, I'll bet you'll find that biology is a theme far more often than physical science.