Hi Sumana,
I asked around about priorities on RFCs in MediaWiki Core's weekly meeting. Nothing popped up, but I made it clear that I plan to be persistent with that question.
I specifically asked about the RCStream RFC, and Tim suggested it does need more discussion. Link for your convenience: https://www.mediawiki.org/wiki/Requests_for_comment/Publishing_the_RecentCha...
We also briefly discussed Structured Logging. It's mainly blocked on the Composer RFC. Once that's done, the structured logging RFC seems to have received adequate review for now; any remaining conversation can happen in the normal course of code review of the structured logging implementation, which is pretty much done.
Rob