His paper on lighthouses is famous (that is why Wikipedia mentions them), in which he tries to demonstrate that for a certain period in England, the coastal lighthouse service, apparently the most public of public goods, was actually supplied by private companies for profit. It should be pointed out that the details of this story are not uncontroversial.
Looking ahead, as conditions in the financial markets normalise further, not all these liquidity measures will be needed to the same extent as during the crisis. Therefore, one should envisage a situation in which the main operational features that were in place prior to the crisis are restored, while of course also bearing in mind the lessons learned from the crisis.