If you read deep into this, they claim much better performance than the built in search; they also imply that the built-in search is missing features they provide but don’t make clear which ones (I think it is just support in the same index for queries covering other conditions on other columns, because every other feature they claim seems to line up with the built in search features, which have been around for about 20 years.)

The built in search can't do any scoring mechanism that involves corpus-wide stats, so things like tfidf and bm25 are right out. If you don't need that then great, but in my experience the results are much worse.

It has it.

Incredible? No.