> What is the carrier for if the jets it carries cannot stop swarms of drones?

What makes you think they can't?

Ignoring some kind of dedicated anti-drone missile systems that they could equip (if you're just hitting drones you could probably carry like 500 tiny missiles or something, who knows), you can just go and destroy whatever platform is carrying the drones, since your carrier aircraft is pretty much going to outrange it by definition.