Modern convoy protection still depends on escort numbers

Have contemporary navies abandoned the concept of convoy protection?

No, but effective convoying needs many escorts, and modern navies usually lack enough spare ships to do it on a large scale.

Modern navies still believe in convoy protection. Recent multinational and Royal Navy escort activity, including operations connected with Somali piracy, shows that the concept remains valid. Force structure is the obstacle because protecting many groups of merchant ships consumes a large number of escorts. Modern navies generally do not possess a surplus large enough to sustain extensive convoy systems alongside their other missions. The same numerical pressure that shaped interwar escort design still applies.