I've sperged about communism before on here so I'll just copypasta my major points:
A lot of communists will point out that technically, communism has never actually existed. Communism is essentially anarchy, where society is classless, stateless, and moneyless. Socialism is meant to provide a transitional stage between capitalism and communism. To Karl Marx, a socialist state is where the means and ends of production are owned by the people, controlled through the state. Eventually, due to the high production levels of the society, everyone would have enough to live happily, and no control by any higher echelons would be exerted.
Of course, we all know what actually happens during this "socialist" stage because we've seen it happen with the Soviet Union, China, and North Korea. Those in the government don't
want to actually become communist because it means giving up their power, authority, and privileges. Thus we get nightmare totalitarian dystopias, because the government currently has all the power and will do whatever is necessary to keep it, even if it means killing thousands of their own citizens.
It doesn't even matter whether communist countries were actually communist or not; we know from history that any attempts to try to implement communism results in warfare, famine, poverty, genocide, corruption, the absence of the most basic human rights (especially freedom of speech), and intense propaganda. I consider myself to be an optimist, and I believe that most people are inherently good, but even I can see that Marx's communist ideals are completely unobtainable.
Plus, honestly, I think communism is just super outdated at this point. Marx lived at a time when factory workers would lose fucking body parts to machinery and still be expected to work through it (seriously, read
The Jungle). People worked themselves to death to make barely enough money to survive anyway, and there was nothing they could do about it. Things aren't perfect today, but worker's rights are taken
very seriously. We can argue about minimum wage, health care, and other financial issues all day, but at least if you get injured on the job due to employer incompetence you can sue the living shit out them. I bet Marx couldn't have dreamed of unions and workers' compensation.