When communism works
Previous reasons for the most common understanding of communism, a humanist dream of happiness, survival, and equality through (sometimes) centralized systems and (often) radical/desperate means (revolutions) with a focus on progress (futurism), becoming a viableAble to compete and one of the only (viable) societal options due to technology.
Rise of centralization: The rise of centralized systems solves multiple historical problems encountered by them, along with making them able to compete with decentralized ones, in the future likely to exceed them (in effectiveness).
Death of people-power: Human obsoleteness (workplace and human hacking) causes the loss of power in the people, thereby allowing dissatisfactory situations (for the people) to occur without (people having) the ability to solve them. Likely to cause in increase in want of good-intent power-holders.
Fear of the elite: Higher power (due to technology) and lowered (people) dependency in power-holders (including resource-holders) allows consphiracies against mankind. Creates a fear of power-holders, especially the ruthless or ill-intent, them being antagonized by communists.
Paradise is near: More technological development and understanding results in the distance (in time) of technological utopia seeming closer. Many brands of communism promise technological utopia to their followers.
Fall of liberalism: Due to various reasons brought by technology, notably inability to compete with centralized systems, many believers of liberalism abandon it. The closest they can come to a progress-endorsing (futurist) inclusive humanist and most importantly viable system is (neo-)communism.
Lack of options: The fall of liberalism is part of the fall of decentralized systems in general, leaving (technological) centralized systems mandatory for effectiveness.
Decline of returnism: old people die
Gradual fall:
Different branding: Not branded as communism. Most likely contender for name is "cybernetic socialism".