Lots of others (I.e., Signal, Threema, etc) including some VPN providers have already implemented quantum-resistant encryption. Apple is just now doing it and they claim there's is the best. Of course, it's proprietary, so can't view source to confirm.
Discussion
Their*
I'm not one of those people I swear
“Yeah my girlfriend is super hot but no you can’t see her, she goes to a different school” vibes
This isn’t Apple who told the FBI to suck a dick after San Bernardino - they’re far too close to the US Gov nowadays and I really don’t trust them much any more
Yeah the secrecy around such a protocol is sus. As long as it’s not openly vetted by multiple cryptography experts, I’ll assume that it’s backdoored by the CIA and NSA.