It's not that the story "should/must"You've been arguing that V's story should always end in failure simply because failure is a theme.
But in Night City (in Mike Pondsmith Cyberpunk) generally (i.e almost always^^), stories end in failures, broken dreams, lost hopes or main characters death.
Those four examples are the rare exceptions and were only possible thanks to V. Above all, V's issue is far more complicated than the problems of these 4 characters, so much complicated that no one is able to help V.
Just my opinion, but I won't bet any coin for another kind of ending in the expansion, if the expansion add one indeed