Hasn't Ruby Central always 'owned' RubyGems.org, Bundler, and all related infra?
Removing existing maintainers from the project isn't good - and hopefully it's a temporary oversight as Ruby Central gets things set up in the new org. Either bad communication from Ruby Central - or they really did made a bad mistake here (maybe even with the best intentions, given recent NPM issues).
Edit: It seems like there's a lot more to the story here. Many volunteer RubyGems/Bundler maintainers have left because they disagree with decisions that Ruby Central (the nonprofit organization) has made and it seems like all of this is fallout related to that.