Would we say that Nemesis wasn't really the "franchise killer"? Oh sure, it killed the TNG movies. But the prime universe continued to exist for a further three years on Enterprise, and Rick Berman was working on another (ultimately abandoned) movie script. If anything, its Enterprise that seems to have killed any goodwill for the Prime universe. That was the last one out of the gate.
I should have said that, given there was insufficient interest in a DS9 or VOY feature film, NEM's failure closed off any possibly of building on 24th century events in the PU, in film. And that closed off any practical possibly of expanding the Prime Universe continuity into the future at all.
Even though ENT was already in a death spiral anyway, as early as 2002, you're right, TATV was the actual whimper that the Prime Universe went out on.