Could naval treaties have preserved sovereign battleships?

The closing question asks whether the postwar treaty system might have created a separate category for sovereign or pre-dreadnought battleships. Older ships had still performed useful work in the First World War, including securing the Channel and operating in the Dardanelles, while Greek examples survived into the Second World War. A hypothetical agreement could have brought Greece and other owners into the Washington Naval Treaty framework while allowing Britain and the United States equal numbers of these second-class battleships. That arrangement creates a bargaining question: would the major powers retain useful older hulls, or exchange their allowance for additional dreadnought tonnage? Formidable's conventional career thus leads into a counterfactual about how treaty definitions can preserve or eliminate an apparently obsolete category of warship.