The question of whether he is a journalist is irrelevant to me. What I do see is that he was a highly partisan actor involved in the affairs of nation states. His behavior around the 2016 election further moved him in the direction of willing accomplice to election interference. His selective publication of data also makes me highly suspicious of his behavior. It all had a very clear slant and focus around the election. He even supposedly solicited information from Russian intelligence agents at one point.
Maybe somewhere in all of Assange's partisan hackery, I can see an argument that he didn't actually do anything wrong. And, since he is very polarizing, you would have to stick to strong principles to still support him and what his legal plight represents. However, I don't think you could engineer a less sympathetic character to carry the banner of freedom of speech/press, which is honestly his biggest problem. No one cares about another partisan hack going by the wayside of a potentially corrupt prosecution. "You get what you deserve". I don't believe that, because I think the actual case against him has merit.
In reality, the accusation, which I believe is credible, is that he was an active conspirator in an effort to steal state secrets, and not just a mild mannered clearing house that published what it got through highly clean and legal means. He broke his own operational "security" code of staying above the fray by being such an active participant in the acquisition of state secrets. The manning case in particular is an area where I believe he crossed the line and was actively assisting and encouraging Manning. He has a hard time telling the truth and based on the facts is morally and ethically bankrupt.
People like Glenn Greenwald managed to handle things like Snowden much more cleanly and without the obvious bias and legal/ethical concerns of an Assange figure.