You're confusing source of revenue with source of value. Both Google and DDG offer value by providing desirable search results (and other services). As I said:

You're confusing source of revenue with source of value. Both Google and DDG offer value by providing desirable search results (and other services). As I said: for both companies, the revenue source is fungible. The core value is not. DDG would still be DDG with a different revenue model. It would not be DDG without search.