After trying to optimize my laptops energy settings under linux, I once also ended up with a device that was operating low level autonomously for some time. It just would not accept commands from me, nor the power button, nor anything else. The CPU also wasn't running, but something was.

In other words it was effectivly a brick to me.

But since it was not a surface pro (I considered buying instead of that one), I could open it and disconnect the battery.

And in effect, unbricking it. Quite trivial fix sure, but nearly impossible with many modern devices, where the battery is glued in.

My point is, not every mode of operation is desired, especially if you cannot change it. Then you might as well have a brick in terms of usefulness.

No. Your laptop was not operating autonomously, by definition.

It was not making its own decisions, to achieve some goal.

Parts of it were. To make some checks for some hardware (as part of an automatic comand line tool). They just got into an infinite loop. Down on the hardware level.

That's not autonomous that's automatic

I think it's reasonable to say that it is operating autonomously and is currently "bricked" as a colloquialism. There's a certain helplessness for NASA in this case, which is similar to bricking one's device. Instead of hoping that the repair shop can fix it, they have to hope that their engineering foresight was adequate.