The paper still holds. It is saying that the natural rate of interest, i.e. the "base case", is zero. It mentions interest on reserves and bond issuance to drai

The paper still holds. It is saying that the natural rate of interest, i.e. the "base case", is zero. It mentions interest on reserves and bond issuance to drain reserves both as ways to "move away from the base case". It claims that, regardless of mechanism, we should justify our actions to move away from the base case. It also claims that the base case is a good policy for a variety of reasons.