Search engines tend to produce neutral garbage, not harmful garbage (i.e. small tidbits of data between an ocean of SEO fluff, rather than completely incorrect facts). LLMs tend to be inaccurate because in an absence of knowledge given by the user, it will sometimes make up knowledge. It's plausible to imagine that they will cover each other's weaknesses: the search engine produces an ocean of mostly-useless data, and the LLM can find the small amount of useful data and interpret that into an answer to your question.