Many of the features users find useful (let's ignore for the moment whether these are good things) like content recommendations and search result recommendation

Many of the features users find useful (let's ignore for the moment whether these are good things) like content recommendations and search result recommendations rely on the same understanding of user interests that allow these companies to target advertisements. So they need to understand your interests anyway to provide the services that people find useful. So they still need forms of tracking to do the things that people find useful on the sites. So what do we do?