That stuff is great but doesn't mean much. Just because they're blocking border agents from trivially imaging phones at the border doesn't mean that they won't cooperate at a higher level with some undocumented baseband features.
Just as Defense in Depth is a concept in security, we've already seen a corollary "Offense in Depth" from the intelligence community. Is the best attack in the random number generator[3] or undocumented silicon[4] or intercepting your boxes on the way to your data center[5] or tapping your fiber[6] or stealing your certs[7] or paying your employees to go rogue[8]? Why choose when you can just do them all.
Apple hardware is vertically integrated and utterly undocumented. The AMT chip has been present on motherboards since 2006[9]. The Snowden Introspection Engine found that the Wifi Chipset remains powered up even when Wifi is turned off.[10] I find it hard to believe that the same government who went to all these lengths to compromise our infrastructure would really let Apple get away with refusing. How did that turn out for Joseph Nacchio?[11]
[1] https://www.washingtonpost.com/world/national-security/us-wa...
[2] https://www.cultofmac.com/498052/ios-11-lets-quickly-disable...
[3] https://en.wikipedia.org/wiki/Random_number_generator_attack...
[4] https://en.wikipedia.org/wiki/Hardware_backdoor#Examples
[5] https://www.extremetech.com/computing/173721-the-nsa-regular...
[6] https://arstechnica.com/tech-policy/2013/10/new-docs-show-ns...
[7] https://nakedsecurity.sophos.com/2013/12/09/serious-security...
[8] http://www.ocweekly.com/news/fbi-used-best-buys-geek-squad-t...
[9] https://libreboot.org/faq.html#intel
[10] https://www.documentcloud.org/documents/2996800-AgainstTheLa...