Socialists argued that wealth and power were consolidated in the hands of too few individuals, that monopolies and trusts controlled too much of the economy, and that owners and investors grew rich while the workers who produced their wealth, despite massive productivity gains and rising national wealth, still suffered from low pay, long hours, and unsafe working condition
I agree with this argument and it is still like this to a certain extent even in modern society. Wealthy CEO's such as Jeff Bezos continue profiting from the work of middle class people who get paid very little compared to what the CEO makes.