It's very simple: a computer controlling a human as a flesh robot instead of the other way around.

Think Amazon drivers, for instance. No autonomy whatsoever, no thinking, no decisions, just eyes, feet, and hands for the machine.

Late stage capitalism existential / body horror, and a wet dream for corporations.

I have no doubt our generation and later will never retire. They'll just plug a chip into our nape and keep our corpses working until they fall apart. 40K was off by 38 centuries.