Re: A weaker system
"Even the NSA's new billion dollar datacenter couldn't come within three orders of magnitude of storing months worth of actual texts and calls"
It easily could.
A single 5TB drive could store an hours' worth of speech a day for 1.3 million people (8kbips sampling). Or 200 disks for the whole US population per day. That probably fits in a single rack or two. Texts could all fit on a usb stick.
I'm sure they have plenty of room in their data centers for 1000's of such disks.