The author examined the distribution of instances in the fediverse. Given that many instances are hidden behind CDNs like Cloudflare or Fastly, the author employed ActivityPub’s functionality to discover the actual hosting locations of servers. More than half (51%) of the fediverse is hosted within a single hosting company. The author suggests that the fediverse hosted mostly with a few major providers, deviates from its initial objectives.
Those companies don’t own your backups and can’t stop you from moving your instance somewhere else. And if you don’t have a backup then it doesn’t matter if you are running your instance in a datacenter you built yourself because you can inadvertently wipe the contents with a mere click