I'm going to merge this into T1928, summary is:
- As a technology, RSS seems to be on the way out.
- Based on talking with people who implemented RSS at Facebook, I'm worried this will take a lot of time to build/support (i.e., there will be a long tail of users complaining that their specific obscure RSS reader doesn't work).
- Authentication is not trivial.
- Overall, this is hard to prioritize because there's limited interest in it, the technology seems to be declining, and the implementation cost is unknown but possibly large.