The fact that he knew what the NSA was doing, utilizing their capabilities to spy on individual for political gain and reporting is correct, however at that time the cabal was in the WH and Snowden would definitely be eliminated, as a whistleblower. Jullien Assange is still locked up in an Embassy after his 2016 reveal.

Both of these men blew the whistle and then had to run for their lives, literally. How else could they survive the repercussion? Its interesting that Snowden ended up Moscow ... not sure if he had to sell secrets to China to get there - hope not, we'll never know.
Desperate times, desperate measures.

Snowden didnt sell secrets. He is a White hat. So is Putin. Don't be shocked when, and if, Q is revealed.

Snowden exposed coms for embedded agents, he then used those coms to identify locations. Just like they did for the press whistleblower program that started this whole mess. (Which Snowden also played a part in) This lead to around 250 embedded agents being killed world wide. He than exposed what he himself had been doing for a long time as a cover story to drum up public sympathy.
If You research where he worked at before going to the NSA, what he actually did there and how many people actually make that full transfer and I think it will paint a much better picture for you of who this traitor truly is.