It’s basically a floating airbase that has the ability to move into (or recede) from combat zones. They don’t really fit our war ethos right now anyway, they are designed to be part of an overwhelming strike in the event of total nuclear war

There’s also ego and competition between the branches and the navy is quite addicted to being an air power and will never acquiesce to going back to “just boats” ever again, if they have their way

Edit: you are totally correct about their redundancy, so I want to clarify: one of the perks of the carrier group is that by moving it won’t be as vulnerable during nuclear war, the enemy has to know where it is, NORAD will always be at NORAD etc

Losing a carrier isn’t just a loss to their “global war on terror/narcos/guys we don’t like” capacity, it’s also a loss to their “oh shit actual peer actual nuclear oh my god war” capacity