Lots of discoveries are confirmatory. We already believed relativity was true before we observed observing binary pulsars obeying it.

No, why? A discovery can fit in with your existing models, maybe even be predicted. You discover it, but you don't change your understanding, only expand it.

You're right of course, but some editor thought it too cumbersome (and not so sensational) to write "fills a major gap in our understanding of the early evolution of eukaryotes", so they wrote "history" instead which allows much more room for the imagination.