What parts of a modern aircraft carrier do you think are redundant? They still need to operate far away from bases and friendly ports (after all, that's the point of a carrier), so they still need nuclear power and to carry fuel for their own escorts. They still need all the radar/radio/command-and-control functions. They still need to be able to maintain their air wing, so they still need hangers, elevators, all of that. (I guess you're arguing for loading a carrier with rugged bush planes and assuming that you could reduce maintenance requirements by doing that, maybe getting to the point of just parking the planes on deck? It's an interesting idea but existing bush planes are generally designed to operate in savannah/desert. I don't know how possible it is to build a plane that can stand up to saltwater spray).
>
As I am understanding it the US is buying such a palne in the Light Attack/Armed Reconnaissance program: https://en.wikipedia.org/wiki/Light_Attack/Armed_Reconnaissa...
Many other countries also use planes like the Embraer EMB 314 Super Tucano[0] to fight insurgents and other that do not have any anti aircraft capabilities.
0: https://en.wikipedia.org/wiki/Embraer_EMB_314_Super_Tucano
If all they're good for anyway is bombing 3rd world countries into submission, hey, just buy a mothballed supertanker, pave it over and load it up with cheap turboprop planes carrying bombs. Equally good for bombing people armed with AK-47's and RPG's, and you'd save billions! :)
And the defensive capability is ultimately the same as a $$$ supercarrier, if the buck in any case stops with "if you touch these, we'll answer with nukes".