While working on [[https://linear.app/comm/issue/ENG-5182 | ENG-5182]], I noticed that we prevent subchannel creation to be announcement channels. From an initial investigation, it looks like it's been disabled since [[ https://phab.comm.dev/D5211 | D5211 ]]. An error is thrown when attempting to create a new subchannel with the announcement setting because it fails the [[ https://github.com/CommE2E/comm/blob/ce4e185558c1a5af773a4291a44b0c6c19c88fcf/keyserver/src/responders/thread-responders.js#L169-L186 | input validation ]].
While this isn't 100% yet, since I need to fix the permissions (especially regarding `voiced`), the subchannels actually are created now, which will be useful in testing.