Their primary target of those apartment blocks was to serve urbanization - to house millions that were moving (or were moved) out of rural villages, with their quite mediocre living conditions, to the industrialized cities. That process was quite ongoing 40 years after Soviet rule was established; lots and lots of peasants in 1950s-1970s USSR lived with a home environment that was quite comparable to early 1900s except with kolkhoz tractors and a propaganda radio. Moving to an apartment with running hot water, indoor toilet, and centralized heating was a major improvement for millions of people during Khruschev era, because their previous dwelling did not have those 'luxuries'.

Before they had khrushchyovkas they had komunalkas. Most everyone is familiar with Doctor Zhivago, aren't they?

That it was. I am under no illusion about the communists.