[snowwrestler]

Apple did try to design encryption that it can't break. But they also want to be able to fix bugs. So they can update the OS on the phone even if it is locked.

So by writing a new update, they could remove some of the ancillary security features that reinforce short passcodes: the "wipe after 10 tries" feature, and the "progressively longer delay between tries" feature. Without these, a numeric (short) passcode can be brute-forced in a day or two. This is what the FBI has been trying to force them to do: write a new update to remove these features. That's what Apple has been refusing to do.

BTW, if you use a long alphanumeric passcode, then it wouldn't matter if Apple was forced to push this update. A 15 character passcode with upper case, lower case, numbers, and symbols would probably be safe from brute forcing no matter how fast someone tries. But most folks are not willing to remember or type in 15 characters on their phone.