I'd made a similarly titled post[1] a couple years back and I seriously don't know what kind of usage DuckDuckGo has right now. But I'd like to think that it is extensively used, at least in the developer community. And I strongly believe that people should start degoogling their lives at least slowly and gradually if its not possible to do it at once. If more people start using DDG, the search engine will improve and that least that one aspect of degoogling could be achieved to a certain extent.
[1] https://news.ycombinator.com/item?id=13284917