Gun safety alternative

A article came out recently saying that gun thefts from cars and tripled in the last 10 according to FBI stats. I am curious how big of a problem people think this is. And I know the obvious answer is don't leave a gun in a car. But with how freely and unregulated making gun free zones is currently( anyone can put up a sign, and you never know for certain, about where you are going), that seems at best irrational. And arguably a perfect way to circumvent the 2nd entirely. What if, to address this threat, we made a gun safe a mandatory feature on all cars, the same way we do seat belts or airbags.