This criticism of marxism is good, it means that ethical humanists can move beyond socialism and maybe even anarchism towards a post-socialist intellectual life. Of course many have done so already and they must be aghast at the scarce progress we are making so it's high time we catch up and get the ball rolling to reject marxism in it's entirety. So what have we learned so far?
1: Wages aren't the cause of wage slavery, neither are they significant "force multipliers" in service of exploitation, in order for the conditions of wage slavery to exist the means of production must be collectivized by the state. Blaming wages is like blaming the knife for a murder.
2: Exploitation and corruption is present in both centrally planned and capitalist modes of production, neither extinguish these problems from society, however centrally planned economies are far more corrupt since they have the top down approach of ideologues and tyrants, sticking their fingers into everything as a policy, as opposed to capitalism where the state is only called apon to solve problems where it can, thus precipitating debate concerning whether the state should intervene and closing most loopholes that the plutocracy can use to facilitate the conditions for wage slavery.