> Power electronics are still modular and are easily swappable.

Depends. These parts are custom designed, physically, and difficult to find off-the-shelf replacements for.

The heater fan-controller on my wife's SUV died. This is simply a current-limiting device: receives (I assume) CAN signals from the dashboard rotary encoder and determines what current to send the fan.

While I could have dragged my 'scope to the car, determine what signals it's getting from the dash system (all integrated, btw), it was easier to find one in China and wait six weeks.

(I may have chosen the first option if this happened in the winter, but in summer the heater is never used anyway).