The last post on UU FB page is dated Aug 2019. I have liked the page and it is not very active. It is only inactive because the 65 users who have liked the page don't contribute much and seem to wait for someone else (including me), which is the way of some FaceBook groups.
I think they are focussing on the YouTube podcast more now. I suggest posting this question on the YouTube channel, but ask in a different format. Instead of asking why you have not had a response, ask them for a status update on the FaceBook page. I think you will get a better answer that way. I have seen the podcasts and interviews where they talk about this forum. They are happy to let UU run and be relatively free without interfering or constantly monitoring for comments, although they will look at threads of interest to them, maybe just like other UU members do. Their current main channel of public communication seems to be the YouTube podcast.