A postwar cruiser-destroyer could have been a durable Royal Navy platform

Was the postwar cruiser-destroyer program a white elephant or a missed opportunity?

A missed opportunity; a sufficiently large Daring-like design built in numbers could have remained useful and upgradeable for decades.

The proposed response to Sverdlov-class cruisers looks like a missed opportunity rather than a white elephant. A large destroyer of roughly 4,500 to 5,000 tons could have developed the Daring concept and been ordered in useful numbers. A possible gun fit used four twin 4.5-inch mountings while retaining space for additional anti-aircraft weapons. The extra size would provide room for upgrades over a long service life. Postwar escorts benefited from growth margin beyond their first weapons fit.