The USSR turned a largely illiterate Russian population to a literate one very quickly. It achieved one of the fastest mass educational transformations in history. In 1917-1920 it went from inheriting a population with 25% literacy to then having 80-90% literacy by 1929-1939.

Not to mention, Proletarianization of Universities (Rabfaks), which accelerated prep schools attached to universities designed specifically for adult factory workers and peasants who lacked formal secondary education. They also built what were essentially trade school-like institutes to rapidly educate people on medical, pedagogical, and polytechnical studies.

I mean, it also had an academic hardcore side to get star students into positions of power and influence, but all successful societies have that. When we see these very same systems in leading capitalist systems like the US, UK, Germany, Japan, or Korea we applaud them for recognizing and empowering talent. Socialist societies are instead somehow criticized for this.

If anything the Soviets were far more serious about educating everyone than their western peers and one of the reasons they become a world power so quickly.