Can you point me to one serious postmodern theorist that holds this view? There are many different views of the postmodern, but rejection of meta-narratives (academic speak for "grand narrative" here) is pretty much universally accepted.
Given how closely this description of post-modernism is associated with Lyotard, one can only surmise that other post-modern authors were, if anything, even less consistent with it.
These are all small micro-master narratives which each have a totalizing perspective and collectively reduce the ‘truth’ to the ‘truth that is out there’ in the intro sequence to the X Files.
Furthermore I would point to his book On Seduction which is is even more accelerationist than Simulacra in that he tells you exactly how to tear the roof down.