Also this message now appears on the pages of every YahooGroup, eg:
groups.yahoo.com/neo/groups/di

> "Starting December 14, 2019 Yahoo Groups will no longer host user created content on its sites."

Some of us have been saying for a long time that forcing platform providers to take legal responsibility for user-generated content some people find objectionable - as if they were publishers not neutral hosts - would have a chilling effect. This may be the first signs of that effect kicking in.