In other words, they're free to do what they want, just as they are now; free market. If you're suggesting that sticking by their guns would become an exercise in futility, that's just the way life works: You can't always get what you want.
I don't think that the right word is choice here. A choice would be agreeing to a proposal between two or more. This is more of a ultimatum, either you join or you quit. Mining on the old and slow chain is pointless though.
Works for me.