Money is a necessary component of capitalism. Capitalism requires money, by definition; money enables profit.
Remember Adam Smith taught us government needed to control things that were too big for the markets to manage; things the markets are not equipped for. Socialism speaks to social ownership of production.
In fact, capitalists pushed for the creation of the Fed because the monitary system needed to be centralized to enable greater wide commerce.
In capitalism, the government's role is to maintain an orderly environment that facilitates proper functioning of markets, among other roles and purposes.
Beyond the prime rate, the market set their rates, through loans, bonds, etc. The prime is the Feds (poor) tool to help manage inflation.
I think people tend to over simplify markets, capitalism, socialism, etc. Economies are extremely complex, and our's is huge.