Surely solving the ready-access to censored content problem would be a good start for our freedom lovin' community?

We have at least 2 (maybe even 3-5) anonymous overlay networks that could be utilized to transport the final solution to this problem (absent copyright regime change). Even plain old BT. Yet curiously, no one seems to be building any solution at scale within them.

rant - just want a bit of music

See above. Or keep on ranting. At least until you convince certain communities to evolve beyond their simpleminded value/ideal of leech and run, speed first (which can actually be quite acceptable).

We need some sort of bit-torrent for censored youtubes, where those who've already downloaded a youtube file, can automatically make it available to others

This is no different than BT with search. An engine to map YT-ID to BT-info hashes is largely moot given you'd know the title to search anyway.