Hardware wallets are good for securing your coins, but when they are made, will core devs add support to the core Monero wallet software? Or will this type of thing not be supported by core software?
I think this depends in large part on what kind of changes would be required. That said, as a first approximation, adding support would seem like a good thing. If the driver program ends up totally separate, it can be a different binary too.
No current plans though. Plans can only be made when we know what the hardware is, what it needs in order to work with the host computer, etc.