What shows shat the bed?
Voyager immediately comes to mind. Its like the writers throw everything about the past 7 years out the window e.g.
Stuff like Picard saving Hugh unwilling to potentially kill the Borg, or the Crystalline Entity which is compared to a whale than "evil".
In the final, "Endgame" Voyager gets to earth, but it was hard, some of her buddies are dead. So Janeway breaks the prime-directive and travels back in time with potential future technology for the Borg, basically ending everyone in that timeline, technically giving the Borg the technology and committing giant massive genocide because the Borg and now cartoon villains of the week with the baddie Borg woman screaming "noooo!".
When Voyager eventually gets back, it ends immediately on that, aside from the episode being all kinds of stupid, it's deeply unsatisfying.
Enterprise had an even worse ending, but that show was never good, so didn't really care.