> In the GitHub table authoritative?

I was under the impression that it is. The post-finalization note points
to it.

srfi-data.scm is the master file containing most of the metadata about
SRFI's. It shouldn't be only on GitHub; it's part of the srfi-common Git
repo. It's not included in https://srfi.schemers.org/srfi.tgz but it
could and probably should be, assuming it's easy enough to add it.