Yea I understand that there's a technical definition that it falls short of, but again they're very explicitly noting that it falls short of that, so I don't see how it's being ambiguous or misleading. And I don't buy that it's not "open" - it's out there in the public; it's open for contribution from the public; it's open to be modified and deployed except if you're a monitoring provider. The OSI doesn't have a monopoly on the definition of the word "open".

Also I think that the assertion that it's "actively harmful" is wildly hyperbolic. Sentry isn't going to be out there copyright trolling people and you know it; they're trying to protect themselves from a very specific category of IP infringement. And there is still much potential upside to it's openness that you're willfully ignoring.