I mean, you can't have your cake and eat it too - if you claim that a particular issue is not a bug and you won't fix it, then you have no ethical grounds to say that it shouldn't be disclosed.
Responsible disclosure expects delaying public disclosure to protect the users while the vendor prepares a fix. If the vendor says that they won't fix it, then it's not only a right, but a moral duty to disclose that vulnerability to the users.
Responsible disclosure expects delaying public disclosure to protect the users while the vendor prepares a fix. If the vendor says that they won't fix it, then it's not only a right, but a moral duty to disclose that vulnerability to the users.