Sure, but the comment I replied to did not talk about a "niche" search engine. If you find a specific area of search that there is no good search engine for, or if existing products are really bad, of course you may succeed in that space, probably because you're at that point targeting the enterprise market -- but expecting normal consumers to pay for a search engine is naive at best.
I would wager that Google's database of new stories is bigger. LexisNexis survives partly through institutional inertia, but also I expect because they've tailored their search product to their specific niche in a way that is much more useful than Google's general-purpose algorithms.
Google's news articles goes back way further than the 70's. They've been scanning newspapers and integrating digitization archives. This is why you can you can look at word usage trends centuries back. But it's not very well integrated into search.