How effective could Courageous and Glorious have been had they survived longer into the Second World War?
Short answerThey could have filled Atlantic carrier roles, freeing newer carriers for harder missions in the Mediterranean and Indian Ocean.
NotesThe strategic value of an older ship depends on whether it can perform a necessary mission well enough, not whether it is the best ship available. Courageous and Glorious could have handled Atlantic work and released modern carriers for more demanding theaters. That extra hull count might have strengthened Somerville's striking power and other distant deployments. The answer is therefore about force allocation across a global war, not a claim that the older carriers matched every capability of newer ships.