posted on December 8th, 2009, 1:33 am
Well ... the REAL answer is that the Borg were supposed to be a massively threatening enemy for the Federation to face. Jumping the Shark too early would have resulted in a bunch of people who watched going: "oh ... there goes the Federation ... hmm .... well I guess that made sense."
Voyager (besides making Borg Cubes look like sissies) did a big favor for the rest of Star Trek by returning the Borg to a state where it's conceivable that they CAN'T send a giant force to Earth and end the show. Now with most of their assets gone, they are in a prime position (story-wise) to be an underdog that becomes a threat again.