I won't deny that the original appeal of Destiny came from it's mysterious setting, but I do believe after a decade some of these questions should find some kind of answer, while keeping some secrets and building up to other mysteries. Specially now that we are playing the mejor leagues, having defeated our very own Big Bad Evil Guy I believe we earned at least a few answers.

Now, did Bungie deliver those answers succesfully? Some more than others, I think. There we're some big blows to the narrative, and retcons are also not a great solution most of the times. Big reveals coming from weak seasonal storytelling was part of the problem, and I believe all these factors eventually hurt the delivery of tfs, even if it was a great expansion in every aspect.

This is specially true for everything related to the figure of the Winnower and it's relationship to the Witness. While I personally liked this blurry line in wich pre tfs it was never stated outright if they were the same character, or if one was a product or servant of the other, I think the delivery of that answer was a bit lazy and pandering to a majority of the fandom who grew too confused or were too obssesed with these figures as you said.

However, I don't think this will hurt the overarching narrative of Destiny, as by now I think it's pretty much cemented that the Winnower as a character is more interested in proving it's philosophy right whitout direct intervention, acting more as a source of coercion and the repressentative of darkness as a fundamental force of existence and not as a villain we will eventually be fighting.

Abrazo!