Honestly... who cares, really. Smart locks aren't about security, they are about convenience. The fact that most residential mechanical locks can be picked in mere seconds by a skilled lock smith with cheap tools should be more concerning. A hacker will need specialized software to hack bluetooth locks, greatly reducing the likelihood of a bad-dooer doing something to your house.
Further, locks don't stop dishonest people from doing dishonest things. You could kick down a door faster than you can pick the lock or bluetooth hack it. Its just a hell of a lot noisier. Locks stop honest people from trying to be dishonest people.