I can on his behalf, because I understand where he's coming from (though I don't agree with the conclusion). I've actually heard this argument a number of times before. Obviously I'm not speaking for him, just my interpretation of where he's coming from.
Snowden revealed the things the NSA was doing that he believed to be illegal. The government agreed that what the NSA was doing was illegal, but no one really knew about it before Snowden revealed it. However in the aftermath, the government decided that while the NSA was doing something illegal, they were doing it because they believed it was necessary, and the government agreed. So they changed the laws to make legal what the NSA had previously been doing illegally. The net result is, everything Snowden warned us about is now legal and nothing has changed.
An unfortunate, unintended consequence, but I would strongly hesitate to blame it on Snowden. If he hadn't said anything, it would have continued, hidden away. If he did say something, it would be codified into law. Net result is, it was going to happen anyway. But at least everyone knows about it now, and I consider that to be a positive.
I think a more accurate description of it is: NSA was acting under the assumption that it was acting legally. The main criticism thrown at metadata collection was that it was a 4th amendment violation. However, a straight forward look at US Supreme Court caselaw shows that it isn't a 4th Amendment violation. The NSA's interpretation was correct.
What they overlooked was that the patriot act section 215, which they relied on for power to ask for metadata records, only allowed to them data related to an investigation. But they were preemptively getting all meta data totally unrelated to any investigation.
So they created a new law to allow the NSA to collect targeted metadata. Which some privacy proponents believe is just as bad, but it's definitely more limited than what the NSA was doing before.
It was never reasonable to believe that the NSA couldn't ever get your meta data. Police can get it for regular investigations too. They just can't get everyone's for no reason.
A key part of any propaganda war is convincing people to abandon the cause. Now that Snowden has stood up, we have no option, as citizens who care about reformation, but to ultimately support him.
Snowden revealed the things the NSA was doing that he believed to be illegal. The government agreed that what the NSA was doing was illegal, but no one really knew about it before Snowden revealed it. However in the aftermath, the government decided that while the NSA was doing something illegal, they were doing it because they believed it was necessary, and the government agreed. So they changed the laws to make legal what the NSA had previously been doing illegally. The net result is, everything Snowden warned us about is now legal and nothing has changed.
An unfortunate, unintended consequence, but I would strongly hesitate to blame it on Snowden. If he hadn't said anything, it would have continued, hidden away. If he did say something, it would be codified into law. Net result is, it was going to happen anyway. But at least everyone knows about it now, and I consider that to be a positive.