People keep suggesting that on the slippery slope of Apple complying with cases of limited scope the next logical step is compelling the production of a signing

People keep suggesting that on the slippery slope of Apple complying with cases of limited scope the next logical step is compelling the production of a signing key. This is the very essence of why a slippery slope is often a logical fallacy, because one does not necessarily follow from the other, and no supporting evidence is given that it would. There are plenty of things that would keep this step from occurring, primary among them that there would be no legal justification - in the context of the All Writs Act, there would already be a solution available to law enforcement that was less burdensome to Apple than providing the keys to the kingdom. I, too, think it is laudable that Apple would fight for privacy, but I also think that a lot of the argumentation around this case is soft and ideological.