I don't know what to tell you. I've flashed on a blank cart and used it on a real NES. Not sure what blank carts have done to circumvent it, but it's no work on my end.
Yes it’s possibke to distribute home brew games by using circumvention. Good luck trying to make that a commercially viable option. That stands up about as well as saying you can distribute iOS apps outside of the App Store for jailbroken phones....