DuckDuckGo is pretty good, is all about privacy and they don't have way less ressources as Apple. But we saw how the launch of Apple Maps was not perfect, so maybe it's easier and better for them to accept the $15B.
How so?
https://help.duckduckgo.com/duckduckgo-help-pages/results/so...
They have their own crawler as well, and there are a bunch of other sources depending on what you're searching for. Bing results are probably a larger part of it at the end of the day, but it's not quite as you are alluding to.
If DuckDuckGo claims to have over hundreds sources, then Bing and Google have over billions of sources by the same definition.