German Federal Government chooses #Nextcloud:
http://www.spiegel.de/netzwelt/web/open-source-software-nextcloud-baut-die-bundescloud-a-1203261.html
and Government of France chooses #matrix:
https://matrix.org/blog/2018/04/26/matrix-and-riot-confirmed-as-the-basis-for-frances-secure-instant-messenger-app/
Hope more governments will follow..