what i don't understand about liberal/left economists is how they don't talk about control of the money supply in class conflict terms

this seems like an obvious thing to socialize: fiat money is granted value by the assent of all (backed by the monopoly on violence of the government) so why on earth allow a barely-concealed private cartel to manage it via credit expansion?

why is it only libertarians who talk about this, typically in terms of private money? maybe I'm just ignorant and there is a lot of content on this topic someone can point me to?