They are worth it. The navy will adapt their tactics to defend them. Armed forces are constantly adapting and integrating new tsctics and weapons.
Hardly. They are obsolete dinosaurs. Ask the Houthis. The USN is being humiliated in the Red Sea. Wait until Putin sends the Houthis some Russian hypersonics and Russian “contractors” to aim and maintain them. That’s all fine, right? You know, like the NATO “contractors” and their ATACMS? The Houthis ended gunboat diplomacy.