@steve @deadsuperhero hey, Steve. Thanks for popping into the conversation.
It's simply untrue that ActivityPub is unmaintained. We handle reports of errors with errata and an editor's draft. The CG published reports on profiles for Webfinger and HTTP Signature this year, and we have task forces for forums, E2EE, data portability, trust and safety, and discovery open now.
We also have the FEP system for building new extensions, and a process for incorporating extensions into the main context.