[numlock86]

> This is what car anti theft devices do AFAIK… why not bikes?

Well, with a car you can easily secure the mechanism because ... well, it's a car. Cars are huge compared to bikes and have enclosures protected from the outside world. Try that with a bike without increasing the weight while making it still hard to just break apart. Oh, and you probably need some energy to make it all work, too. Also there's costs and chip shortage. But yeah, main point is to make it actually secure within the given space and dimensions.