At the same time, it's also understandable how a security start-up, upon (rightly) getting fed up waiting, decide to publicly disclose, as a way to scrape some PR out of the sunk cost. Public disclosure has a place. But if you truly care about helping, you could do more than bumping on HackerOne and messaging the CISO once on LinkedIn.
Maybe I'm too cynical but it truly feels like nobody actually cares at this point.