Who the fuck cares if it's not from "pureness of his heart"? Why are we holding him to an infinitely higher standard than the bastards in the US gov't who were doing all the spying that Snowden uncovered?
guy leaks secret info about how US agencies surveil Americans and the world. in public's eye what they do is bad or illegal and what he did is at least illegal. it's a draw at best because many Americans consider national security important.
If he faces prosecution after leaking = guy fights authorities for good cause, has high ground, and it is a pretty controversial bipartisan case.
but he runs to a country that literally benefits from his report and then supports him by offering asylum (which it rarely does) and permanent residency and citizenship (even more rare) = support for him is less popular and more partisan