I agree. Here's what Steve Jobs had to say about this, in the context of mobile search: https://www.youtube.com/watch?v=JC8LR9cryG0

If we assume that different search queries are better served by different engines then I wonder if it's not possible for someone to develop a "thin" search engine that would do semantic analysis of the query and then redirect it to one or more sites, or show results side by side...