Having control over your own search index and ads network makes all the difference in the world.
This has done a lot of damage to DDG. When the vast majority of your faithful users are concerned about their privacy and a certain amount are downright paranoid it does not go well when they learn that there are secret exceptions to that privacy.
What has been broken with DDG is that one-click install and you are protected belief.
That said, DDG search might still be better than most others for privacy.
https://digdeeper.neocities.org/ghost/search.html