There are basically 4 search engines left in the whole world - Baidu (China), Yandex (Russia, recently officially with KGB management), Google and Bing. That is all, full stop. Everyone else is a fancy GUI for on them. Google has more than 90% market share and each of the rest has like 1-3%. Building new engine is prohibitively costly and hard. So the lesser evil is Bing, by simple elimination.