His life literally depends on Putin's whims - a situation which the USA and EU have forced him into. How could you possibly fault him for not poking the bear that he was forced in a cage with?

Not really, he'd be risking whats left of his life by doing so.

There's also rather little reason for Snowden to bother commenting on the very widely known abuses by Russian government, what could he possibly have to offer on that topic that hasn't already been said?