The CIA dump apparently contains malware stolen from other countries. So perhaps if/when wikileaks starts releasing them, that'll include Russian/Chinese malware.

It may also be that they simply have far smaller security states, with fewer people who feel alarm at the extent of what's happening. Or maybe leaking to Wikileaks just isn't in vogue in those countries.

Russia and China have not got their stuff leaked, yet. Punishments in those countries are far more severe, too.

While one cannot expect editorial independence from Wikileaks, I believe the language and cultural barrier also plays an important part

Not to mention those with that access level on those countries wouldn't release any information like that "for free"

My feeling - based on reading only publicly-available resources - is that China and Russia rely more on more traditional "HUMINT" (Human Intelligence), while the US has come to rely more and more and "SIGINT" (Signals Intelligence).

There was recently a leak from BND (Germany) all documents in Germant. No one enjoys reading German.

Maybe in Russia and China such leaks would be punishable with death penalty effectively.