What a loaded question. Hero is such a poorly defined yet super high bar. Firefighters who die rescuing children don’t even typically want to be called a hero. This just sets up people to say no and muddy the water.

Did he stand up for democracy and transparency and rule of law? Yes. Did he suffer for his actions from powerful people more concerns for the political harm caused by the exposure of illegal actions? Yes.

Did he do everything right? No, he’s human, and wasnt asking to be lionized or elected anything. He wanted people to look at the materials and demand change from governments. He didn’t get what he wanted, and ended up stuck in Russia, where people can dismiss him as just a traitor, so no, he didn’t do everything right. He could have also thrown himself on the mercy of the American justice system, no matter how doomed that would be. But he’s human, so I don’t expect suicide.