I will try to answer mostly PS. This question is wrong because you address only the "theory" of communism. That is what communists writers write. These ideas indeed had attracted many people in the past, and even attract some nowadays.
However the hatred of communism is mostly based on its PRACTICE, not on the theory. Communist regimes, ALL of them, without exception, mean deprivation of people of freedom, and mass murders on the scale not comparable with any other ideology. Read the history of Soviet Union, China, Cambodia, Eastern European communist regimes, Korea, Vietnam and so on. If you want a condensed exposition, read the book "Black Book of Communism". The authors just collected the facts.
Of course one can ask why is there an apparent discrepancy between communist theory and communist practice. Well, whenever such discrepancy appears one should conclude that the theory is wrong.
There is one country by the way where people can choose to live in a communist society freely. And come back to the normal society if they wish. This is Israel.
About 100000 of Israelis 1.2% of poulation, live in 270 communes called kibuzzim. They are organized on the principles of communist society, more or less.
No one has a slightest objection to this.
But when communists begin to ENFORCE their ideas on the rest of population, this always leads to mass murders, starvation and other similar consequences.