My thoughts would be that if the fork resulted in a different network, then it would follow that it would want its own forum to discuss their network.
But this would not stop them coming here and discussing issue , since the forum is open to SAFE users and non users alike.
But obviously since the forum exists to discuss SAFE and also about its technical aspects, all discussions that are purely about a fork would be off-topic. It would have to be examined at the time it happens as to how it is handled.
And the forum rules would still apply so any trolling of topics to promote the fork or demeaning the SAFE network would be dealt with according to the forum guidelines.
But basically they would not be “shown the door” or any thing like that.
But of course there can be forks that do not result in a different network and I would say that discussion would have its category and any specific topics on the fork would be done there.
Someone may do a fork to incorporate a different sign in procedure, could even allow automated sign in for IoT devices. Who knows there maybe a number of these (minor) forks