In other kind of content like datapacks, resourcepacks and blogs we have the option to publish that content as ourselves or as a group we are in and have permission to upload content in, but I think this option would be added to forum threads too, because recently I've found some forum threads related to a PMC group but that are published by one member of the group, but I think adding the option to publish a forum thread as a group could help to promote those groups but would also help to keep order about topics related to those groups.

With this, forum threads widget could be added to groups too and not only members, so that would help to groups' sites visitors to find more topics related to those groups quickly from the same group page.