How a costly Belgrano gun action could change later warship armament

What effect would a surface engagement with General Belgrano have on later ship design?

A costly gun action could reinforce the demand for deck guns and encourage heavier armament or twin mounts.

The Falklands War already strengthened the argument for retaining deck guns on Royal Navy ships. In this counterfactual, a costly engagement with General Belgrano would give that argument a more dramatic example. Ships exhausting their missiles and then fighting with guns could prompt demands for a stronger gun battery. Twin mounts are suggested as one possible response to that hypothetical battle.