OpenSimulator has been around since 2007. It doesn't have federation in the sense that servers freely send and receive content and VR compatibility isn't built into most clients, but it works as an open standard, and could use a lot of support toward that end.
Btw a free and open source federated vrchat like social vr game would be really cool. But I am just a dumbass who hasn't learned 2 code
OpenSimulator has been around since 2007. It doesn't have federation in the sense that servers freely send and receive content and VR compatibility isn't built into most clients, but it works as an open standard, and could use a lot of support toward that end.