BT standard wasn't even that bad, from security stand-point, the worst thing is implementation and maybe only SW implementation.
Televisions(eg.: LG) where you're unable to turn BT off. With that knowledge, you can buy cheap device which is normally used for development and analyzing of BT communication.
And with that device, you can spam any TV around you with fake BT connection requests, TV is basically unusable during this time and best thing, this cannot be blocked :D
(only way to turn BT off on LG TV is with you getting root and downloading homebrew app, which of course degrade the use of your TV remote, because it uses BT)