In the three decades Stalin was general secretary, the Soviet Union had enormous economic growth. Russia went from being a backward peasant country ruled by a czar, to being the first country to send a satellite to space. Its success and its example were what was feared. While unemployment was 25% in the US in 1933, the USSR was charging forward, and US and European firms and workers were going there to work.

On Stalin's death, Khrushchev announced economic growth was no longer a priority, and other such policies, and stagnation set in.

China also had enormous economic development under the communist party from 1949 to 1978, and from 1978 to now (although the party took a right turn under Deng Xiaoping in 1978, to where some question if China was socialist after then).

The average inflation-adjusted hourly wage in the US is below what it was 45 years ago, leading to anti free trade Trump and Bernie Sanders and Alexandria Ocasio Cortez. Also Corbyn, Syriza, Brexit, ping-pong from Lula to Bolsonaro, TARP bank bailouts plus the carbon externalities destroying the planet.

Of course, I don't think a traditional Marxist worldwide communist revolution of factory workers led by Leninist parties will happen.

The present economic system might be eradicated though. It has not been all that long since European kings were having their heads chopped off or were being bayoneted to death in basements.