Maybe just not indexing and rendering?
[..]The right question would be, who decides what information is reliable and what is unreliable
Google itself cannot determine which information is reliable and which is not. First, it is conceptually wrong for Google to decide for users of their search engine (read: “for all”) what is true and what is not. Secondly, in practice, it is not feasible for Google to validate all the pages you link to (read: “the whole Internet”).
This is also the answer to your second question: No one party makes that decision, and that’s a consensus among many different parties, some more important than others. The most important parties depend not only on location (the US, Europe, Russia and China don’t always agree on what’s real), but also on the target group (what applies to a person who votes Republican is not always the same as true for Democrats).
Google’s search engine basically does two things: crawl the entire Internet (it doesn’t matter what’s true and what nonsense is; everything goes into the index) and sorts the search results (a lot of things run like, “This makes sense. Or is this bullshit?” could be a factor). In an older version of the search engine, I used something called “page rank”. In short: the more Aharon Pages are related to something, the higher you rank in search results. (How to do this these days is more secretive than launch codes, but it seems very likely that “who links to this” still plays an important role.) This means, however, that Google cannot choose to display “block” search results. , because the way to judge the credibility of those research results is to know how related they are. How do you get links to a page? That’s right, because people (on google.com!) search for information, read it, form an opinion about it, and then link to it or not on their own pages. If you want Google (and other search engines) to only show reliable results, you’re basically in a chicken-and-egg situation.
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