Why can the United states government seize a darknet site based in another region of the world under different governing laws? I would understand if they were like "hey thats illegal here I'm going to ban americans from using this site" but they are like "hey thats illegal here, I'm going to screw over the whole world." (But of course we are all law abiding citizens who just enjoy their privacy on a market filled with their peers.)
In international politics, one has such rights as one takes or is given. Don't over think it. U. S. asked. Other country complied.