I don’t think anyone can host a relay right now aside from bluesky.
People can host their own data / Personal Data Server, which is somewhere between self-hosting a mastodon instance and creating an account on someone else’s instance. The actual equivalent would be self-hosting your masto account separately from any instance (which is just not a thing with the current state of mastodon nor activity pub).
Interesting news, to be sure. It’s a shame that the article’s “What People Are Saying” section is really “what high-placed Russian officials are saying”.
Thank you, OP, for sharing an archive link.