Earlier quoted context omitted.
There's a difference between releasing everything, and only releasing stuff Russia wants you to release, like Assange was doing.
That's not true. Wikileaks was releasing all sorts of documents. I think the stuff about western governments just got a lot more attention because it broke through carefully crafted narratives and beliefs that people had about those governments. If some info about Russian corruption was released on Wikileaks, most Russians would be like "I already know most of these government people are corrupt, what is the news?"
So it's basically Assange working as a political agent of Russia and knowing it.