Yes to this. I once had a neat little idea I put into my first fantasy novel as a throwaway line: every few thousands years, the universe switches its basic operating principle from rational cause-and-effect to magic, or vice versa. To me, it explained how Isaac Newton started out as an alchemist and ended up as a giant of the Enlightenment.
Years later, when I needed a novum for a story, I revived the idea and made it the problem of a far-future Sherlock Holmesean detective. I sold the story, then another,, then another. I’ve just sold a tenth story about this character to Lightspeed and in between there were three novels, published by Night Shade.
What sustained reader interest? The complexity of the character’s dilemma: he’s a superb rationalist, but once magic reclaims its power, he’ll be a dunce in the new world. He struggles to deal with that, and it’s the struggles, not the novum, that makes the series work.