Its similar to the credit cards contactless. New trend is that if you have it in your pocket someone can come very close to you with a reader and get 30£ ... they even make phone cases and walets that prevent this from happening by using materials to block the signal . I bet soon there will be key car covers...
But looking back there was steering locks , gearshifter blokades, etc etc... and they all got a way to brake and steal the car.
Common sense seem to be the only way at the moment to not leave stuff in the car, keep keys safe,...