That's not investigative journalism. It's much closer to muckraking.
The ones that had so cozy of a relationship with the Pentagon that they saw no problem in being government mouthpieces and getting the public to support a war in Iraq that killed 200k+ people on a made up pretense of WMDs. Same for Lybia, Syria etc.?
Because that's how you get the level of government access to be what you'd consider a 'real' journalist.
I am glad that you don't get to define who makes a 'real' journalist and who doesn't. Julian is not one of these[1] indeed.
I consider that journalistic malpractice. Like I said, investigative journalism is difficult. People, including the "real ones" sometimes do it badly. When they do, the good ones apologize and retract.
For what its worth, I don't actually think that you'd need particular government access to do a reasonable job of censoring the names of at risk agents in the documents wikileaks leaked. I'd go far enough to say that me, as a layperson, with practically no journalistic experience could do a better job than Assange did. In fact, I'm certain of that.
That's disqualifying. He didn't even try.