This is wrong. Marxists do not have the right ideas. They have terrible ideas. Their ideas degrade the dignity of mankind as individuals. Their ideas destroy individual rights.
Marx was a slothful, angry, violent person who let his children go hungry rather than work for a living, sponged off of Engles for most of his life, knocked up his maid and left her and his child destitute.
The Marxist ideal is not only unworkable, it is unholy.
Marxists have the right ideas for the wrong species.
Their theory might work for beings with identical DNA, gender, talent, ambition and appetite for risk.
Humans are not that species.