I'm not a lawyer (and law can be tricky), but forcing a company to do something impossible (breaking into a truly secure device) seems very clearly to be a "undue burden". The real issue here is that Apple has created a device that is possible for them to backdoor themselves, and the clear solution is to remove that capability from future devices.
[1] https://en.wikipedia.org/wiki/All_Writs_Act#Conditions_for_u...
Apple screwed themselves by not creating lets say double signed bootloaders - the code must be signed by the owner and by apple to run. In that case the only probable attack is microcode on the cpu or apple saying to the federal government - here are the transistors you need - good luck getting to them - we don't have the equipment to dig in microchips.
But if you accept that evolution of the internet in this direction in inevitable and a natural process of history, then this is like saying that "there's nothing stopping the government from issuing orders that gravity be temporarily disabled."
I don't accept that the evolution of the internet in the direction of consumer devices with manufacturer-unbreakable security is inevitable, particularly in the face of governments actively punishing manufacturers for failing to break into devices at the governments' demand.
In fact, I would argue that such an evolution is quite evitable.