DDG is my default search engine, i quite like it.
But, you and I live in different galaxies if you think DDG is Bing's key to gaining market share. DDGs value of privacy and no filter bubbles, is not a compelling (or even understandable) concept to an overwhelming majority of users. Facebook proves this.
Even to those who understand it, the value of DDG is variable. I tried DDG for a few weeks, but switched back to google simply because I was actually having to sort through more results than the specialized results that google gives me.
I like feeling that my privacy is preserved on DDG but I'm still debating whether or not it's an acceptable trade-off for search result relevancy for me.
my hunch is the former is their goal...