DS9 had a larger plot, each of which eventually carried a season and showed the evolution of the entire run. There were important stories toward the larger story and then there was filler.
Voyager didn't have a larger plot. Everything was filler.
If Nogs development is unimportant because it was filler, then everything from Voyager is unimportant because it was all filler inbetween the pilot and the finale. Nothing of consequense happened in between Caretaker and Endgame, except Janeway changing her hair cut, the mobile emitter, Seven swapping out with Kes and the delta Flier, which are all quite superficial.