Sure, the car toys are not easy to crash with each other. On the other hand, take a single car and send it [preferably fast] towards any kitchen appliance that reaches the floor.. Have fun prying the neodymium magnet from it.

If they’re that powerful it will also repel any metal on you preventing you from getting to the car.

I had this idea decades ago - magnets surrounding the impact areas of the cars front, rear and sides, which would repel another vehicle employing the same magnet system. It wouldn’t prevent all collisions, but would severely decrease the energy upon impact.