In 1998 there were plenty of search engines and their use was distributed more evenly. The internet was still fairly new and most people weren't online yet. It certainly wasn't an integral part of most people's life. Google came along and improved on the existing search engines and in doing so wiped out a lot of that competition, becoming what they are today.
A new search engine now has to compete with global network effects, orders of magnitudes more data, Android, and a complex web of interconnected functionality.
Even only looking at the advantage that Google Maps brings to the table totally blows past any barriers present in 1998. Sure, you could build a much better search engine but who's going to use it when it can't give them directions?
Then consider that if you look like you'll end up making some headway, you're likely to just get bought and killed off/integrated.