BUT… I kinda do. You want the lowest PWM frequency you can get away with. In this case, at the back of the car, furthest from the battery, you really don’t want a 8kHz PWM nor do you need it. It costs money to isolate the supply demand, so you don’t want a noisy field for no reason. The “good enough” frame rate is 60Hz static, not moving, no other flashing lights, not using a camera, etc.
60Hz or 60fps has issues though. If you expose a PWM LED to another flashing light or movement you get really bad imaging. Imagine you took an LED in your hand and shook it, at 60 Hz you will see snapshots of where the LED was as you’re shaking it. At 240Hz you will see a blur. Guess which is better for a vehicle?
I figure most car LED taillights internal to their housing would be 200-1000Hz depending on factors but I haven’t ever measured.
200Hz PWM is a really common value. No need for Samaritan base-12 here.
For halogen and incandescent, we use PWM, fun fact. Low Hz though! About 88Hz, depending on voltage. You might wonder why. We can get 98% of the light output with 85% of the required wire. It’s all about weight and cost. Although not many vehicles use this anymore.