Demonstrably, it did not.
Fission is still a "mega" project, and it's Dangerous (for assorted values of Dangerous). Which made it also very expensive.
Traveller Fusion is of the Mr. Fusion variety to the point that vehicles have it built in, rather than running on batteries. There's a fusion generator parked outside of people houses, shopping centers, elementary schools, and government offices. And that's AOK.
"Yes, sir, it's fine to park your fusion powered car in the garage beneath the court room, but you'll need to leave that pen knife and tweezers at home."
Meanwhile, Fission is like coal. Nasty, dirty, and best kept away from people.
There was never any call for dotting nuclear fission generators across, say, Africa (where environmental regulations and, shall we say, "quite lax").
Now, we're simply coating the planet with solar panels.