This isn't currently supported. You can see progress toward it here:
Except, of course, that I can't, because I (don't have a (Facebook|Disqus|phabricator.org)|prefer not to use my (GitHub|Google)) account. I'm sure I'm not the only one who hits this wall.
"policy.allow-public" affects future settings which will be available in the UIs built by T603.
Could you perhaps summarize what that means, time-wise? Is there anything we (I) can do to push things forward?