It's worth noting the distinction between the auth layer and the data layer here. Tangled uses ATProto primarily for authentication, but it departs from the standard PDS model by offloading Git storage to knots.
While that's a clever hybrid, Bitchat is aiming for a truly serverless, local-first experience (especially with the Bluetooth mesh aspect). Radicle’s gossip-based P2P stack mirrors that vision more closely. In this case, Radicle isn't "better" in a vacuum—it's just the right tool for a project that wants to eliminate mediating servers entirely.