Same reason you don't get turned into a thin red smear on your driver's seat now when someone taps the front bumper of your car.
Just because a solution to a problem exists means nothing if the company involved is too cheap to implement it. Even if that means the consumer is the victim.
History has shown over and over that most companies don't give a crap unless ordered to.
show me a device that NHTSA has invented and then required that automakers implement on their vehicles.
every safety device, whether active or passive, was invented by private industry and in order to pay for the R&D involved (millions of dollars at a minimum) they charge extra for it. example - Subaru's Eye Sight Camera which virtually eliminates rear end collisions. they charge an extra $2,000 for this feature. when the government steps in and makes it mandatory, it doesn't mean you are getting it for free. the automaker just increases the price of the car. so whether it's law or not, the fault always falls with the consumer who isn't willing to pay extra for whatever safety measure is being offered. so the government steps in and makes them. that's how it works
you went into an industry that my career is in so i suggest you go with another example to prove your point, otherwise you will drown in facts that i will throw at you.
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Activation lock came in ios7 this time last year, the figures I'm quoting are from this year
Find my iPhone came out in 2010....