I am not an XSF member, yet I am interested to
reinstate XHTML-IM.
I am very much in favour of this. While deprecation in favour of
https://xmpp.org/extensions/xep-0393.html may have seemed simpler at the
time, new work like
https://xmpp.org/extensions/xep-0394.html demonstrates
that this is not enough and there is an appetite for full rich text. The
standardized rich tezt format is HTML which has the benefit (for us) of
having an obvious XML syntax and a pre existing XEP.
Besides this we also have new and acitve uses of XHTML-IM in the community
(not just by me) and leaving the XEP deprecated is confusing in this
context.