All of the main Fallout lore (1, 2, 3, and New Vegas) is 1950’s-esque. The nuclear war that destroyed the world did not occur until 2077. What caused the culture to stay static for that roughly 120-year period?
I know about the lack of transistors, but that doesn’t explain everything.
The Fallout universe is intended to be a purely fictional representation of what people in the 1950s thought the future was going to look like. As such, there's no "explanation" for why culture stayed that way other than that's how people in the 50's lived:
The Fallout world is much like Torg - physics and natural laws are not the same as in our universe, but are based instead on 50s sensibilities and pulp era comics - the Fallout universe is what people in the 50s believed the future would be (with a lot of nuclear warheads dropped on it).
The Fallout setting was heavily influenced by a 1950's science fiction anthology called the Worlds of Tomorrow.
There were two major differences between the history of the "real world" and the Fallout universe, one of which you've already hit on:
Pre-war Fallout is a vision of what would have happened without the miniaturization allowed by transistors, meaning most of the electronic advances of the 70s forward could not have happened. Would we have the same kind of music if there were no synthesizers, turntables, guitar effects pedals, CDs, iPods, etc? What would cars look like if everything running them was still big and mechnical? Fallout is Black Isle's attempt to guess what that might be.
Post-war Fallout is essentially what people during the "Red Scare" thought the world would be like if there was a nuclear war in the 1950s, it just didn't happen in-universe until 2077.
if it helps to justify things, i can probably assume that somewhere along the line the culture was deliberately stagnated as part of various possible social experiments done by the government during wartime and continued on into the vaults. i dont think any of the vaults were equipped for handling more creative minds. after all, there was only one single vault dedicated to holding the most talented wartime musicians and artists who were then promptly subjugated to brainwashing experiments while the rest of the other vaults were only outfitted with basic essentials and whatever was needed for each respective social experiments.
and then after exiting the vaults, and giving credit to the hypocritical brotherhood of steel, almost every postwar society is going to be some form of cult or tribe based off what the survivors of the vaults were conditioned to, and lacking ways to express creativity due to reasons, either immediately degenerate into tribals and cultists or attempt to imitate and appropriate whatever they immediately find on the surface.
I would imagine that the drug explosion of the 60's never occurred in that universe. That is seen by many as the cause of the drastic changes in American culture then. But as the first answer said, it is supposed to characterize what people thought the future would be like when they were in the 50's.
I think in the fallout universe, the nuclear meltdown of Chernobyl never occurred, thus nuclear power was never seen as a threat to the human race. In that the Cold War never ended, and the two countries kept building and building they're nuclear arsenal and nuclear powered nations
The fact that the culture of Fallouts is from 1950's, yet the year of the war is 2077, is probably a way for the developers to explain the fact that workers have been listening to Frank Sinatra while creating power armor - to make the post-apocalyptic universe filled with '50's references while still having all the high-tech. We could even speculate that, if the American society had the same attitude towards the communists throughout those 120 years, then a nuclear war would be unavoidable, since the US would not try to disarm the rest of the world of its atom bombs, with the Red Scare at height, making China expand its atomic arsenal to be on the same level of power as the US and Russia. If we assume that the Chinese mentality ALSO continued throughout 1950-2077 untouched, then we have a good explanation for the atomic war - both superpowers hating each other and arming themselves to the teeth. It's poorly explained how Russian-Chinese relations are Pre-War - it's not even known which side USSR picked during the Sino-American War.
