That's comparing apples to oranges...
My point being is that a finale for any show doesn't have to solve the problems set forth by the pilot. A finale rather should be much more about completing the personal journeys of the cast. And, the thing is, completing a journey doesn't necessarily mean that you got to your goal, too. That's what DS9 and Breaking Bad did, among other shows. Characters are more of a priority because characters are what make the narrative, *especially* for a serialized show.
If Breaking Bad doesn't work for you as an analogy, I'd posit All Good Things. Major test, cosmic consequences, just another day on the Enterprise. Q is on the verge of saying that the past seven years were all for naught, despite the central theme of exploring strange new worlds and new civilizations. Rather, what Q was addressing, and what Picard realized, wasn't physical exploration that Trek is known for and what was put forward in Encounter at Farpoint, but exploration of self and the ability to consider the impossible -- not quite Trek in the literal sense, but only Picard, arguably Trek's greatest and most idealistic explorer, could have solved that riddle. Q had to come back from the perspective of the pilot to lay down the idea that our heroes misinterpreted or failed the premise of the pilot, and that the answer lied in Picard's own personal growth. In Breaking Bad, the meth isn't
really the problem, even though it's a terrible drug with a hellish addiction. Rather, the real problem is Walt's inner conflict of love of family vs. thirst for power and respect. The kind of guy who would resort to making meth isn't going to be a good guy, and that's carried through to the end.
In my mind, Bajor is a bit analogous to, say, the Philippines. The Spanish and other countries like Japan conquered and subjugated it, like the Cardassians. The US helped free it like the Federation and assumed that one day the Philippines would like to join them and put up a military outpost, like DS9. Other countries would love to have the Philippines under their rule; the US for years waffled and debated about having the Philippines as a US territory like Guam. Eventually though, and after a lengthy war, the Philippines opted not to join the US, but to exercise its sovereign right to independence and cultural identity. The US honored that but pledged to offer its protection and support when needed, like Starfleet, with the outpost still there. If this were fiction, one would think that the series finale would have the Philippines on the way to US statehood, but historically and truthfully, its series finale had the underdog civilization pushing back against colonizer and supporter* alike to stand on its own. Bajor, over the course of seven seasons, had thought very much about the Federation, but to themselves they earned the right to push their own. To their credit, the Federation honored that -- it wasn't seven years of work down the drain, but seven years of work helping a planet come to its own after so much destruction. That in itself is a fitting finale. If a finale is supposed to see the completion or next steps of its major characters, I'd posit that the finale treated Bajor itself as a character, too, ready to explore the next chapter of its life just as much as O'Brien, Odo, Worf, and Jake. Bajor's goal -- whether it's full independence or joining the Federation -- is less important than Bajor's story built up and its willingness to see its next steps through.
On the flip side, I wasn't so satisfied with Endgame precisely because while it ended the journeys for, say, Janeway, Paris, and Torres, it tried to resolve things that were created virtually yesterday for Chakotay and Seven. And "These are the Voyages" wasn't really about the NX-01 crew, it was about Riker doing cosplay to solve his problem, which is much smaller than the drama in birthing the Federation. Remove the TNG framing device altogether, use that extra time to build up everyone's end story, and you'd have at least a decent episode, because then you have the emphasis brought back to the crew we had come to know over the past 4 years.
(*with a shit ton of political caveats, but that's an essay for later)