Why does all the Fallout games stuck in the 60s?

The reason behind the retro look and the 2070s setting of Fallout is the slower advancement of technology and the frequent conflicts. In my view, the Fallout series takes place in a parallel universe where World War 2 might have lasted longer than in our reality. The consistent repetition of the line "war never ends" in every Fallout game strongly suggests this explanation.
Why does all the Fallout games stuck in the 60s?
Why does all the Fallout games stuck in the 60s?
Post Opinion