Sure genius, the American working class was the world's aristocracy of labor, after WW2. If you know your history, the US came out of the war unscathed, unlike the Soviets who lost 28 million people and much of the infrastructure that they had built in the previous twenty years. During the great depression in the US and Western Europe, the Soviets were actually doing quite well, to the point that thousands of American and Western European engineers and scientists migrated to Stalin's Soviet Russia, to contribute to the new nation's development.
After WW2, the Soviets had to pick themselves up by their own bootstraps and rebuild their new country. Unlike Western Europe and Japan, the Soviets didn't have the "Marshal Plan", funded by the US, to help them redevelop their countries. The Soviets had to do it on their own, and in less than 15 years, it was a nuclear power, launching the first satellites and even people into space.
The Soviets despite all of the challenges built their economy to the point that it was the second largest economy in the world by 1970, only second to the USA. Not bad for a new country, constantly being economically sanctioned and attacked militarily by powerful, well established, older, much more entrenched, and developed enemies, like the USA, huh? The US had over 100 years of industrialization ahead of the USSR.
If you notice, Berlin was in Eastern Germany, a part of Germany that was communist, and for security reasons primarily the wall was built. They had American, British, and French forces in the heart of their country, so they built a wall around Berlin. Now if you claim that it was also built to keep people from East Germany defecting into Western-controlled Berlin, you are partly correct. I'm not going to deny it and lie to you.
So let me get this straight, you invest your resources in training scientists, engineers, and doctors, to serve your country, when it is trying to get back on its feet after a devastating world war, that killed 14% of your population (28 million people), and the enemy across your border is constantly tempting those highly educated and trained citizens of your country, to defect and drain your nation of its intelligentsia and academics. It's called "brain drain", and yes East Germany and the USSR did restrict travel outside of its borders for its citizens., as a matter of survival.
The USSR was essentially always at war, in an existential battle against extremely powerful enemies. If it wasn't a hot war, it was a cold war, draining resources that could've been used to improve the lives of Soviet citizens.
What your capitalist propaganda does not tell you is that despite those restrictions, Soviet citizens still did travel outside of the USSR, and also extensively within the USSR, which was an enormous country, with many different interesting places to visit.