While this presentation would be an acceptable variation of an author's name provided in the RFC header, I have concerns about how xml2rfc would handle the creation of reference entries. Currently it adds periods when a period doesn't exist in the fullname or initials attribute of the author element because sometimes writers can miss these.

For example, the following reference from RFC 8650 (note the lack of periods in fullname="I Hickson" and initials="I"):

        <reference anchor="W3C-20150203" target="https://www.w3.org/TR/2015/REC-eventsource-20150203/" quoteTitle="true" derivedAnchor="W3C-20150203">
          <front>
            <title>Server-Sent Events</title>
            <author fullname="I Hickson" initials="I" surname="Hickson">
              <organization showOnFrontPage="true"/>
            </author>
            <date day="03" month="February" year="2015"/>
          </front>
          <seriesInfo name="W3C" value="Recommendation"/>
          <annotation>Latest version available at &lt;<eref target="https://www.w3.org/TR/eventsource/"/>&gt;.</annotation>
        </reference>

Is rendered as "Hickson, I.,":

   [W3C-20150203]
              Hickson, I., "Server-Sent Events", W3C Recommendation, 3
              February 2015,
              <https://www.w3.org/TR/2015/REC-eventsource-20150203/>.
              Latest version available at <https://www.w3.org/TR/
              eventsource/>.

If an author wants their name to appear as "J. Doe" (with the period) in Authors' Addresses section, could they still do that with fullname="J. Doe"?

I have not touched the codepath if initials is set. Those will still always be rendered with a trailing period. So, either an author sets the initials field to "J", or puts the full name as "J. Doe".

@ajeanmahoney This change affects references as well.
With this change:

<author fullname="J Doe" surname="Doe">

will generate:

Doe, J, "Title..

And,

<author fullname="J Doe" initials="J" surname="Doe">

will generate:

Doe, J., "Tile..

Would
<author fullname="John Doe" surname="Doe">
generate
Doe, J, "Title...
or
Doe, J., "Title...

We see instances of the following in non-RFC bibxml entries:

<author fullname="Christopher Meyer" surname="Meyer">
   <organization>Physical Measurement Laboratory</organization>
</author>

With my code, it would generate Doe, J., "Title....

If I read this correctly this would render a fullname of Axxx B Cyy Dzzz as A. B C. Dzzz. I don't think this is a problem.
(Well I do, as I think we should stop manipulating names altogether, but that's beyond the scope of this PR)

According to my tests, yes that's what it'll do.