We’re still talking past one another. I never said there are really existing things. I just think your language about “existence” is overly strict, and also alien to the early texts, where temporary phenomena do “exist” in a non-“real”, non-inherent way.
All that exists (in experience) are dependently originated processes, not independently, truly existing things. And when these processes cease, it is not annihilation because no thing was destroyed. Your logical step from nothingness to annihilation is incorrect.
In my view, according to the Buddha the result of parinibbāna is no type of experience or awareness, i.e. there is nothing left. If you don’t agree with that, then it seems there are two options. Either you think the Buddha didn’t know/care/explain what happens after parinibbāna, or you think there is still something remaining afterwards. In the latter case it is that which holds that there is a truly, inherently existing thing—namely something that remains.
In other words, it is exactly because there are no truly existing things that parinibbāna can end in nothingness. If there were such things, then this wouldn’t be the case, because inherently existing things can’t cease (otherwise they wouldn’t truly exist). And also, if parinibbāna ended in some kind of mind or experience, then that itself would be the truly existing thing.
That’s why cessation of empty processes is the middle teaching.
I think this is exactly what Nāgārjuna teaches, although with a different use of words, which is why I don’t have fundamental objections to these teachings. The wrong views of atthitā and natthitā in the suttas are synonyms for eternalism and annihilationism. Both entail a self—or in Nāgārjuna’s language, truly existing entities. My view, like yours, is that such selves/things don’t exist. But neither of the two views is that mere dependently originated processes cease without any truly existent thing remaining. That is not what natthitā is about.
I would ask, how could there be no truly existent things yet nibbāna still be something? If you agree that nibbāna is not something, then it is nothing. Those are the only logical possibilities in ordinary (i.e. non-Nāgārjuna) language. That’s why earlier I tried to press you on this point, to take a stand on the matter. You acknowledged that it is possible to talk in, let’s say, “non-ultimate” way, yet didn’t say what your position is on this.
I don’t really mind either way, but I think it will be generally useful for any discussion if we don’t assume the other has said things they didn’t.