Karl Marx was correct in many assumptions and predictions. Humanity throughout human history has always been swinging to the left of the spectrum. You don't have to be communist, or even socialist to understand this principle. Evolutionary Socialism will lead to Communism. Marx and Engels were right about the world.
Capitalism is a form of slavery, in which those with money own labor from those who need money. The working class is always in need of money and thus must work their entire lives, without much choice about the matter. At some point the working class must stand up and demand greater equality. Karl Marx is right in many ways, though not without flaws
I think it is quite clear with all the economic troubles that besiege us today may suggest that Karl Marx might have predicted this. The working class seem to have a dimmer future than that of the capitalists and maybe it is because they have become so greedy that they just do not care.
People claim the working class is enslaved in the $7 minimum wage. This is false. If you want a higher paying job, go and get job skills and a education. Don't act like you deserve a lot of money for doing a job literally anyone can do. Equal rights =/= Equal pay. It's crazy how people feel entitled to everything. Nothing in life is free. A lot of rich people built their fortune from nothing.