Thanks for your extensive answer. (Had almost missed it seeing the short version on Twitter and initially not recognizing the importance of the link at the end.)
Yes, a group effort would require the group also deciding what is important. I guess that is the main difference with personal IndieWeb homepages. Curation, categorization, prioritization.
Something Reddit-like or newspaper-like would be needed. I guess we have the technology, but we would need a design to make it work.