Thank you for sharing your work and great to see more attempts on the same problem. I am one of the maintainers of the Radicle project.

The main problem we encountered with similar systems that rely on blockchains / dht for storage is the problem of 'blockchain poisoning'.

This is when someone deliberately adds illegal content to an append-only source in hopes to make the sole act of replicating the project legally problematic, as correctly pointed out by Konstantin Ryabitsev of the Linux foundation with regards to a previous version of Radicle that was relying on IPFS. see https://radicle.community/t/the-radicle-social-model/317