"Just" shoving things into firmware at least means the closed-source code runs on a different CPU, often (but not always) isolated from main memory, often (but

"Just" shoving things into firmware at least means the closed-source code runs on a different CPU, often (but not always) isolated from main memory, often (but not always) with no network access, which the main CPU often (but not always) has the ability to power-cycle.