I took the time to read the entire article. The fact that he took the Tier 3 data is extremely troubling. The fact that he shared that knowledge with a reporter for the SCMP is damning. The only countries who would profit from that particular Tier 3 data are China and Russia.
Glad you read the full article. I assume you have added insight being an IT guy. I also find the details unnerving.
My gut is that Snowden intended for China and Russia to have the NSA's crown jewels. I suspect he did this out of massive ego and a misguided desire for revenge. He have also been unwittingly manipulated by a Russian operative from within one of his hacker circles.
My guess is that Snowden ultimately desired to manipulate and misdirect everyone, the NSA, his friends, journalist, the public, and even the Chinese and Russians as some sort of affirmation of his own brilliance. Unfortunately for him, the professionals in the FSB and SVR are much better at these sort of games.