i get what you mean
i'm aware not everything can be toggleable but when it involves the world it should be possible to toggle it off that isn't from Basegame (Willow Creek, Oasis Springs and Newcrest should stay) maybe you don't use the world itself but you do love to use the pack for other things or you want to focus on 1 specific pack only that comes with the world
each their own opinion of course but i bet one day it will be unplayable for everybody, even the newer pc's so it should be optional to toggle the world on/off without actually deleting the pack (if you do change your mind or if you're done with a certain pack that comes with the world, you can toggle the other one on again while turning the other off)
just a thought though