It's already been demonstrated that when people believe a given thing, they will go out of their way to *continue* believing that thing. Even if you show them an overwhelming amount of evidence that they are wrong, rather than convincing them to change their opinion, they will instead double-down on their existing belief.
Combine that with the fact that there is a ridiculous amount of crap out there, from 'vaccines cause autism' idiots to Fox News, we *need* some kind of filtering to eliminate the nonsense that is put up there with the explicit purpose of misinforming people.
The only concern against something like this, is how easily/likely it would be for governments to subvert for pushing propoganda.
Of course, the end result will probably be that people stop using Google, cause being able to confirm their bias is far more important to people than the search engine they use.