Having spent my whole life in electronics, I'm very much pro-PCB. Especially in amps. But in guitars, I have mixed emotions. They could be good in some situations, (control cavity), and bad in others, (Strat pickguard mounted components). I'd hate to see pots soldered to a PCB. They'd be hard to change out, and you'd have to remove the whole assembly to change just one. Also, on the couple of LP's that I've done that had those connectors, there was no way the connector would fit through the pup wire hole in the body. That means the connector was added after the pup was installed. Kinda defeats the purpose, IMHO.
It's not a bad idea, but would need to be implemented very carefully.
I think good engineers who also play guitar and are interested in ergonomics and marketing could make it work. We are pretty limited with the setups we have now. There are standard switching schemes, and we are more or less forced to accept them. Imagine easy ways to transform what a 5 or 6 position does per gig? Of course it can be done.