What central banks can control is a base and one way they can control the base is via manipulating a particular interest rate, such as a Federal Funds rate, the overnight rate at which banks lend to one another. But they use that control to control what happens to the quantity of money. There is no disagreement.
Milton FriedmanDoing good with other people's money has two basic flaws. In the first place, you never spend anybody else's money as carefully as you spend your own. So a large fraction of that money is inevitably wasted. In the second place, and equally important, you cannot do good with other people's money unless you first get the money away from them. So that force - sending a policeman to take the money from somebody's pocket - is fundamentally at the basis of the philosophy of the welfare state.
Milton FriedmanFundamentally, there are only two ways of coordinating the economic activities of millions. One is central direction involving the use of coercion - the technique of the army and of the modern totalitarian state. The other is voluntary cooperation of individuals - the technique of the marketplace.
Milton Friedman