Google (as it originally) existed wasn't a source of information, it was an *index* of it. You were trusting google as a source for {search_query}, you were trusting the links it gave as a source (based on your own evaluation). LLMs are fundamentally different, because you are trusting the software to actually generate the information in a truthful way.
If you use google (sans AI), you're putting some trust in their page ranking algorithm. If you use it with AI, you're trusting the same algorithm (since that's how the model gets it's sources), but then you're trusting the model to evaluate the sources for credibility and extract the information you actually want.