Obviously, we'd have processes built that build machines for each of the individual tasks, or changing tracks to support new car models.
From my perspective, this framework of a factory could map to many other endeavours where we either produce the end product or a machine used for something else.
So, the difference would be whether the machines utilize chemical/biological processes for working, or are made out of steel, at which point it would boil down to economics.
I guess I don't see what's so special about adding 'bio' to these perpetual factories.