The Gold Rush
With the secret of the Black Box Drive revealed, an era of frantically searching the belt for huge iridium deposits started. Although some iridium was discovered, no one ever came close to finding anything that would make a dent in Black Ocean's monopoly.
While other companies were busy trying to find iridium, Black Ocean steadily established the rare metal as the new gold standard of the solar system. Ship drives improved, and so did the actual ships themselves. Although some previous failed attempts were made in the 21st century with relatively ancient technology, humanity was finally ready to truly become an interplanetary species.