He took specific steps (cracking a hash) with the clear intent of helping break into a government owned computer system.

I'm not sure what the gray area is supposed to be here.

If I teach you lock picking skills as a fun hobby, that's clearly okay.

If I teach you lock picking skills knowing you aspire to be a house robber, that is grayish legally and wrong ethically.

But if I break into a specific bank vault for you to help you steal stuff, and we talked about stealing the stuff before I helped you, then I'm clearly involved in a criminal conspiracy.

Assange committed a crime, and if he played the same role in helping to empty your bank account you'd want these laws to exist.

The ethical question here is about whether that crime was ethically jusified. I.e., it's about civil disobedience, not about whether blatant conspiracy should be legal.