Nanotech has already destroyed science fiction, at least the science fiction it has touched. Not because of the technology, but because of what it does to stories and plot lines.
To write entertaining and gripping stories, the writer needs tension and drama. How can a writer control their audience and guide them through a story with nanotech on the scene? At any moment, nearly anything can happen. Our Hero can suddenly grow a suit of armor, he can have nanobots in his body that spontaneously destroy the poison he is given, he can open a vial that destroys a planet in days. Our Heroine can be attacked by the air she breathes, be in possesion of killer panty hose, use lipstick as a weapon or have her fingernails morph into stainless steel overnight.
Nobody worries about plausibility any more (such as what happens to the binding energy of atomic bonds when a nano machine either assembles or disassembles atomic structure - energy isn't for free, even at the quantum level - and too little isn't as bad as too much). It's just too easy to wave a hand and say "nanotechnology makes it work". They may as well be saying "prayer makes it work" or "magic makes it work".
To make it work, writers have to create some kind of structure, some rules that give order to their nanotech narrative, else it just disassembles into a hodge-podge of goo. In a normal story, without nanotech, the world has rules and order that keep things sane. Inventing this order and inserting it into a story, without being heavy-handed and clumsy, is more than most writers are up to. At best a few writers, on a few rare occasions, have held the chaos of anything-goes nanotech at bay long enough to turn out a decent story. Not very often, however, and even the writers who have done the best have failed on other occasions. Nanotech, aside from it's real-world capabilities, clearly has the ability to totally consume a plot line.
About the only thing worse for plot lines than nanotech is the holodeck...