What a load of bullsh!te. It's not about the medium, it's the fact that it's an ongoing story line. You are whining like a little ***** about "not getting closure" and "waiting around for the ending" when it is not the job of the TV writers to prematurely conclude an ongoing comic book.
If you don't like it, stop watching. Simple as that.
As for your ignorance about Spider-Man...oh my lord..."there's only so many villains for him to defeat"? Are you insane? The movies have been rebooted because of rights issues and/or actor/director availability, not because of "villain scarcity". ****, they could make an entire trilogy of just different characters who have worn the Green Goblin costume (Norman, Harry, Harry's psychiatrist, etc.), let alone the enormous villains list the Spider-Man has.
Nobody is arguing the GENERAL issue of TV shows lasting nearly a decade. Actors get sick of it too, thus the rise of 10-episode seasons over 22-episode seasons.
But you are whining about cutting 20 minutes out of a 73 episode series because it's "slower" for certain bits.
Come on, enjoy the last 6 episodes and quit complaining. Or just turn it off. If you don't have an extra 20 minutes of attention-span, this wasn't the series for you.