The fundamental point of divergence in the Fallout universe was not "nuclear power becomes commonplace but the transistor is not discovered for decades," nor was it the specific ways in which the first Red Scare and Cold War played out
Rather, the Fallout timeline diverged from our own bc they started getting swamped by a ceaseless slew of godawful remakes, reboots, and re-releases in the '70s instead of the 2010s
in Fallout 3, New Vegas and Fallout 4 combined, there was maybe one original, diegetic song. everything else is replays. this points to a dystopia in which rap, disco, electronica, and modern rock and roll were never able to come into existence at all, regardless of whether they were later suppressed