Not that the controller board on a washing machine is particularly exotic; it's made from standard components. But each model of washing machine has it's own controller board, so the boards are low-volume, and ridiculously expensive. And the boards themselves are about as easy to repair as any modern PCB covered in SMDs.
I suspect the reason that white goods nowadays all have digital displays and digital control panels is that those "features" necessitate a proprietary controller board, which turns out (surprisingly! /s) to be the component most likely to fail.
