After all Hams hate not being part of something that they think holds an advantage.
More likely by far is that they join the free parts of the network that are sure to spring up. At the very least, spots will "leak" in various ways, or some will support the new network but still have a free option. There will be paths that manage to get around the registration and still let all comers put in spots somehow. Or, maybe just a straightforward alternate free and hassle free
form of spoting. How do I know? Because that's what happens when this sort of thing is tried, especially with highly technical people. We can't foresee all the reasons this will arise, but history says it will even if
you ignore people like me that think it is ridiculous.
But, in the end, there is no ability to prevent the erection of alternate paths for this information. The premise that this can be controlled is wholly mistaken.
We don't need Balkanization of spotting. We just need. . . spots. The rest is agonizing over nothing and the assertion of control that will not control.