Most vehicles are mechanically capable of going that fast because thats how fast cars can go when they are given the amount of power that consumers want when accelerating to pass or merge.
Most vehicles do have software speed limiters, which are typically set to the safe mechanical limits of the vehicle when manufactured (often, the speed rating of the tires).
The reason software speed limiters are not set to the highway speed limits in the US is because:
1. They might be used in places other than on highways subject to US law
Most vehicles do have software speed limiters, which are typically set to the safe mechanical limits of the vehicle when manufactured (often, the speed rating of the tires).
The reason software speed limiters are not set to the highway speed limits in the US is because:
1. They might be used in places other than on highways subject to US law
2. Laws change
3. Manufacturers are not required to