I've emailed the IETF HTTP WG with a proposal to adopt the Braid-HTTP spec here:
https://lists.w3.org/Archives/Public/ietf-http-wg/2023OctDec/0120.html
I'll be giving a talk on this at the meeting next week, on either Thursday or Friday, in Prague. Rahul Gupta will be in the same session, presenting his kindred PREP specification.
Thanks and congratulations to everyone who's contributed!
Michael