And face it, for all its flaws, Google's index is larger, it has more servers, has way more signals to use - including its own web browser, DNS and ads - more money to spend and actual computer scientists who've been banging away at the problem for decades. Bing is just Microsoft's way of siphoning off some search revenues from the most technically illiterate users who don't know better and never change their defaults on their Windows box they bought at Walmart. MS has zero incentive to improve the results.
DDG is a cute little boutique web site. Good for them. But their impact on Google Search is so small as to be non-existent.