Not many people know this, but Mao Zedong's famous pamphlet, Combat Liberalism, was actually a treatise on why the downvote should be removed from all social media platforms.

To indulge in irresponsible criticism in private instead of actively putting forward one's suggestions to the organization. To say nothing to people to their faces but to gossip behind their backs, or to say nothing at a meeting but to gossip afterwards. To show no regard at all for the principles of collective life but to follow one's own inclination. This is a second type.

To hear incorrect views without rebutting them and even to hear counter-revolutionary remarks without reporting them, but instead to take them calmly as if nothing had happened. This is a sixth type.

To see someone harming the interests of the masses and yet not feel indignant, or dissuade or stop him or reason with him, but to allow him to continue. This is an eighth type.