Not to argue that this is a good thing, but to expand: the UX of having your ad purchaser decide how best to target a demographic is really bad, so Google abstr

Not to argue that this is a good thing, but to expand: the UX of having your ad purchaser decide how best to target a demographic is really bad, so Google abstracted it away. For example, you might not know that only homeowners in Minnesota like to buy cheese, but you want to sell cheese to Minnesotans, so Google will automatically target your ad to homeowners. It doesn't need to know the former fact explicitly either; it's just a large correlation matrix that they learn on the fly.