Let’s just use the simple binary of complete cessation, which means nothing after parinibbāna, Vs anything left, even realifying nibbāna itself. Clearly it’s either one or the other.
Any if there can be confusion, it’s likely the imprecise terminological usage of nibbāna with remainder vs nibbāna without remainder (parinibbāna). Or conflating the psychological usage of nibbāna is the highest happiness, safety etc with it must be something ontologically positive. Whereas in one sutta on comparison of happiness of the jhanas, arupas and cessation of perception and feeling, one person asked why is it called higher happiness when there is no feeling? The answer is because there is no feeling that it is called the higher happiness.
So ontologically negative of no feeling can be described using positive terms like happiness.
It’s important to get the Nibbāna view right because if there’s anything leftover at all after parinibbāna, it is permanent, eternal. Thus it has been always there even before parinibbāna, even before arahanthood, even before stream entry. Thus it can be regarded as the true self. Yet, there’s a sutta which says there is not even a little bit that is unchanging, thus nothing can be called a true self.
The delusion of self can happily park itself in parinibbāna if there is a conception of something leftover, and due to the delusion of self is not being destroyed utterly, the view of self that takes Nibbāna itself as self, then that blocks the way to stream entry.