Physical (de)centralization of XMPP servers – we took 1000+ XMPP servers and looked at their hosters:
https://gist.github.com/infosec-handbook/19f96587511d6d8ab79b564a7e0b3bdf
– about 50% of these servers are hosted by only 7 companies in 3 countries
– logical decentralization obviously doesn't imply physical decentralization
– more than 50% of servers are hosted in Germany, followed by the USA (10%) and France (7%)