Forked brains would lack the security and guaranty of the main chain. Virtual minds will have also some needs, to communicate for example, to hear and see the world.
Hacked and forked minds would be kept secretly(without communication with the outside world) in a kind of slavery just for exploiting them.
Their blockchain would be a slavery chain.
![Sad](https://bitcointalk.org/Smileys/default/sad.gif)
Slavery is evil even in the virtual life.