I don't really understand the Pirate Bay part. Torrent websites rarely if ever host anything copyright infringing. They're just a way to discover and access such material.

When people say they "got xyz from there", that is a simplification. It means that the site has successfully brokered them to a swarm with the desired bit of data, not that the site / site operators have actually served them any of that data. They solicitate copyright infringement, but not necessarily (usually?) engage in it. No bits of copyright data travelling through their assets necessary.

It's like trying to catch a fixer on a consumption charge. They don't possess the drugs, they don't distribute the drugs, they don't purchase the drugs, they don't consume the drugs. They only handle information. It's a derivate, associable conduct, not the conduct itself.

To speak about the legality of unmodified and modified proxying of such content then simply doesn't seem sensible to me, or related.

(2019)