It's worth pointing out that Maxim Dounin is, by himself, likely critical mass for Nginx. Since he started in 2011 he is by far the most active contributor to the codebase.
Surely "Nginx" is trademarked, copyrighted, etc. A cool and collected fork would do some basic work to avoid trivial lawsuits, consider the other forks already in the space, and write up a bit on how this fork will be different from the others.
Russia has laws on the books that allow them to exempt domestic operations from international IP enforcement and to nullify any damages if the entity has a connection to an "unfriendly state."
Of course it is not mentioned, it is implied. The term "rage-fork" is a made up one, not sure whether anyone else uses it in this form. But if you imply that there was no rage in the decision to fork - well that's something to have doubts about and it very much seems the move was done with some significant emotion in it. although somewhat concealed in the original post.
Everyone has a right to forking the project. Only time will tell if they get critical mass of developers to keep it going.