Simplest solution: don't store anything you would not want to fall into anyone else's hands on a tiny mobile device.
Whether this thing is legal or not, whether it's ethical or not, whether we hate it because Apple probably will or we love it because it's able to beat Apple's encryption system... etc, we can't stop it by whining about it in a thread. Easiest defeat of anything like this is to NOT have anything on your phone that you don't want to get out if the wrong people got your phone.
Apple buying one of these and finding a way to defeat it doesn't automatically stop the next one... and there's always a next one. In fact, there's probably multiple versions of THIS one and we're just hearing about this one because it's probably the oldest one.
Earlier today, there was a thread about new Intel chips defeating variants of chip-level exploits. Great right? Until new variants come out that sufficiently differ from those variants to no longer be protected by whatever Intel did. That's the game there: secured:unsecured, secured:unsecured.
Same here. Apple can buy one and adjust the code to beat it... but then the next one rolls out to beat Apple's code. However, if we don't store anything on a mobile device that we would not want the bad guys to be able to see, no exploit would matter anymore.