I agree that if they hadn't done something with the Borg, it would have been a missed opportunity. But see post 145
. Basically, Anwar shot himself in the foot by claiming that the Borg was a concept inherently incapable of being handled well more than a couple times.
Well, isn't that why folks think Voyager weakened the Borg?
Due to Voyager getting around them AND Janeway, Tuvok & B'Elanna being assimilated and saved with no long term scars kinda supported showing them a few to many times weakened their fear factor. The more we learned about them, the less of a true threat they seemed. They're the Jason Voohees of Trek. IT went from: "Eek! It's Jason. Too: "Oh, is he back AGAIN!?!"
Even looking back on TNG, "I, Borg & Decent" are pretty stupid stories and already started to make the Borg look like idiots.