Something to chew on:
When ENT's final season produced "In A Mirror, Darkly, Parts I & II," it totally contradicted the SCE stories "Interphase, Parts I & II." Yet that didn't mean the entire SCE series ended; those two stories ceased to be referenced but the series continued.
Same thing with "The Aenar" that season also establishing that Andor was a moon with a much colder climate than had been depicted in Worlds of DS9. They stopped referencing the idea that Andor had a tropical climate, but nothing else from that story was nullified.
Obviously the situation with PIC is a bit different. PIC may well contradict a lot of major elements of the Litverse. But it's also possible that key points may remain but in new forms. Like there's no reason yet to assume that the Titan crew is any different or that most TTN novels didn't happen.