Species 8472 showed us that it is very far from futile. Just go check the hundreds of ships and thousands of worlds that they destroyed. Then there's the four known pathogens that destroyed cubes, and eventually, the entire unicomplex.
In short, resistance is only futile for those less advanced species.
Not to mention that Starfleet managed to successfully resist in virtually every on-screen encounter they ever had with the Borg, though most of them were costly.
In TNG resistance was futile, in Voyager Cubes became somehow cute. And of course Starfleet wins in the long run, otherwise the complete franchise would end :P
Not to mention several Starfleet people who were able to de-assimilate (Jean-Luc Picard, Seven of Nine, Kathryn Janeway, Tuvok, etc.)
+ Dr. Phlox
Read the Destiny trilogy in the end every member of the collective is freed and abosorbed into the Caeliar civilization proving resistance is not futile.
In ST:VOY Endgame Voyager uses a tanswarp conduit to return to the Alpha Quadrant. In the process they destroy loads of Borg and Borg technology including the Queen. Four Borg children were also deassimilated as well as the characters mentioned above.