The only value in responsible disclosure is protection of users. If you figure out there's a way to harm a boatload of people, it's nice to do what you can to ensure it can't happen before telling everybody how. It makes sense. But there's a very good reason it comes with a not-too-distant deadline before you give up on it.
But this? We're talking about finding ways that people are being actively harmed. How does "responsible disclosure" come into play here?
The only thing it would seem to do is to protect companies and their bad decisions. That's not the point. At best they've screwed up, and at worst they're actively malicious. How do users not deserve to know that they are being harmed as soon as possible? How do potential users not deserve to know that they will be harmed by using the product, and that the company is either doing a poor job of protecting them or actively trying to exploit them?
There's no reason to try to attach any ideas of "responsible disclosure" here unless you're explicitly trying to protect the vendor.