notice how they aren't publishing leaks of any kind of quality for the last several years.
They helped Snowden get out of the US and then from Hong Kong to Russia, and then helped him to stay there with his girlfriend. That was only June 2013, so clearly they have been doing some very useful work in the "last several years".
Wikileaks can only leak what people give to them. You can't really blame them for not releasing more stuff, since it's not like they write it themselves.