You're saying as knowing what the "truth" is is an obvious thing, and anybody could do it, and anybody could recognize whether certain statement is "truth" or not. But it is far from being the case. Many very smart and very honest people routinely disagree on many subjects whether something is truth or not, and on top of that many people also make statements that may look like truth but turn out not to be after detailed and complicated investigation. You can not expect an owner of the search engine to be the arbiter in these disagreements and to perform those investigations. And even if they did, who would ensure they themselves are being objective and not just enacting their own biases and hiding facts that they think are inconvenient to them? How do you observe this fact? The truth may be not subjective, in a pure Platonic sense, but our knowledge about it and our trust in ways how to get to it certainly would be.