“Whatever Feds have as a backdoor a thief will enter through, tech proverb.”
Not so.
One can have a device-based key, so you would need the device itself.
Or you could have a two-part key, one part with the manufacturer and another part with the NSA.
Or you could have a three-part key, one part with the manufacturer and another part with the FBI and a third part with the NSA.
One could also have the user enter a portion of the key, which might be saved to the manufacturers website.
So even if a Communist lackey gave the PLA every key code entered in Apples factory in China, the phone would still be secure against criminals.
Apple could also enter codes in the USA.
Obviously, a financial institution has the code(s) to my chipped VISA card.
Is my chipped VISA card secure against thieves? Yes.
Obama thanks you for your support.