Because it is a machine and has no agency.

Same as why if you ask someone to stab you and they do they are liable for it, but if you do it yourself you don't get to blame the knife manufacturer.

At every step there is human agency involved. People came up with the idea, people wrote the code, people deployed the code, people saw the consequences and were like "this is fine".

This is why people hate us. It's like Schrodinger's Code: we don't want responsibility for the code we write, except we very much do want to make a pile of money from it as if we were responsible for it, and which of those you get depends on whether the observer is one who notices that code has bad consequences or whether it's our bank account.

This is more like building an autonomous vehicle "MEGA MASHERBOT 5000" with a dozen twenty-feet-wide spinning razor-sharp blades weighing fifty tons each, setting it down a city street, watching it obliterate people into bloody chunks and houses into rubble and being like "well, nobody could have seen that coming" - two seconds before we go collect piles of notes from the smashed ATMs.

>[B]ureaucrats can be expected to embrace a technology that helps to create the illusion that decisions are not under their control. Because of its seeming intelligence and impartiality, a computer has an almost magical tendency to direct attention away from the people in charge of bureaucratic functions and toward itself, as if the computer were the true source of authority. A bureaucrat armed with a computer is the unacknowledged legislator of our age, and a terrible burden to bear. We cannot dismiss the possibility that, if Adolf Eichmann had been able to say that it was not he but a battery of computers that directed the Jews to the appropriate crematoria, he might never have been asked to answer for his actions. Neil Postman, Technopoly

Entities shouldn't be able to outsource liability for their decisions or actions — including the action of releasing stochastic parrots on society at large — on computers. We have precedent that occupations which make important decisions that put lives at risk (doctors, ATC, engineers for example) can be held accountable for the consequences of their actions if it is the result of negligence. Maybe it's time to see include computer engineers in that group.

They've been allowed to move fast and break things for way too long.