Pirate Bay is one hydra of many
Virgin Media, my cable ISP, do block Pirate Bay as I notice if I look at the tracker tab during my regular TV show download sessions. That doesn't matter though since there are usually at least four or more other trackers available, often with thousands of seeds/peers. The hydra's heads have lots of little heads, it's amazing and quite inspiring to watch.
I think the concentration on Pirate Bay is just sound bite politics from government and other organisations that want to be seen to be doing something without actually achieving anything that has a real effect.