Let's go to the metaphorical tape
USSR: Literacy went from 25% (for Russia) in 1917 to 90% in 1939. Country went from 4% (for Russia) with access to electricity in 1917 to 100% in 1940. Invented LED, pioneered space travel, contributed mightily to medical care and development around the world, and invented peaceful use of nuclear fission as well as first working nuclear fusion reactors.
Yugoslavia: averaged over 6% annual GDP growth for more than 30 years.
Albania: ended centuries-old tribal blood feuds. 1st country to eliminate taxation.
Bulgaria: gross agricultural product more than doubled between 1948 and 1970.
Poland: went from 11% of students graduating 7th grade, fewer than 80,000 teachers, and 0 medical schools in 1948 to 26% of students attending college, more than 170,000 teachers, and 10 medical schools in 1963. More than doubled the number of teachers over the same interval.
N. Korea: Averaged over 25% annual GDP growth over a 10-year period. Achieved and continues to maintain world's highest literacy rate. Eliminated taxation.
Czechoslovakia: 11% increase in life expectancy and 33% reduction in infant mortality between 1948 and 1985. First country to eradicate polio, using research done in the USSR.
Hungary: annual inflation rate of over 40 quadrillion percent in 1946 to less than 3 percent by 1956.
E. Germany: first country to eliminate homelessness. Built power plants in dozens of countries.
China: eliminated foot binding. Land ownership more than doubled. Literacy roughly quadrupled between 1949 and 1999. Invented practical fiber-optic communication and synthesis of insulin. Achieved better than 6% annual economic growth over a 50-year period including 34 years of annual growth over 10%, making its the fastest-growing economy in the world. Percent of people owning bicycles went from less than 0.1% in 1949 to 36% in 1989. 94% increase in life expectancy and 83% reduction in infant mortality between 1949 and 1974. One of 2 OECD-classified "developing countries" to become reclassified as a "developed country."
Vietnam: Achieved nearly 5% annual economic growth over a 20-year period. Malaria death rate cut by a factor of 20. Life expectancy rose 49% and infant mortality cut by 85% between 1950 and 2016 despite the deadly effects of American chemical warfare. Multiplied the number in college by a factor of 10 between 1950 and 2021. Reduced poverty rate by 74% between 1975 and 2010. One of 2 OECD-classified "developing countries" to become reclassified as a "developed country."
Cuba: eliminated homelessness. First country to mechanically harvest sugar. Created immunotherapy treatment for lung cancer. Brought eyesight to hundreds of thousands of blind people. Increased literacy by 25% between 1959 and 1962. Pioneered access to college classes on television. Nearly doubled the percentage of children enrolled in school between 1959 and 1986. Increased life expectancy by 23% and reduced infant mortality by 91% between 1961 and 2015. Achieved lowest HIV infection rate, lowest crime rate, and lowest extreme poverty rate in the Western Hemisphere. Achieved world's highest rates of abortion and divorce. Only country considered to have sustainable economic development by the World Wildlife Fund.