Although I do understand where you guys are going at and I don't mean to crash the party but....
The locks aren't made by car companies to begin with as well as the factory radios, seats, or wheels.
A lot of car companies has outsourced their audio equipment decades ago to pioneer, alpine, or some other company. Of course 95% of these cars are equipped with low tier stuff that can't touch real aftermarket stuff.
Since when have we seen "Ford tires" or "Nissian tires"? Never because they don't make it. It is pretty common to see car companies switch tires on a newer year car even if it is the same generation.
There is a handful of cars out there with their seats made by companies like Brembo. Although Brembo makes high end bucket seats they also make some OEM stuff. I know the 8th gen Honda Civic Si has some comfty bucket seats made mostly by Brembo. I think the STi seats is made by Brembo as well.
Car locks I am not too sure really.
Delco radios. But they still have options...like Bose, etc... MS does the same, they give basics that work and let you upgrade from there.