I suspect the big problem is that even if your search engine succeeds, once you get enough traction you'll just sell up to Google and everything slots back to normal 'do some evil' mode.

I don't want to get too off-topic, but personally I can promise you we will never sell to Google. This problem is very personal. As well as being a programmer, I used to work as a journalist, and I've seen friends in media have their lives and businesses destroyed by Google's ad-tech. And I've seen the Internet turn from a wonderful thing to become a cesspool of content farms, clickbait and seo spam. I can't speak for other search startups, but we will never run ads or use ad-tech or sell user data or invade people's privacy. We're just two people. But we're two people on a mission.