The Economist has been doing anonymous articles for about 100 years, I think the only difference is they are not controversial.
Not the same thing. Economist articles, with the exception of special reports and the farewell article by the editor in chief, are not bylined . The reason being that the newspaper wants to speak with one voice. In addition, and being certified and proud opinion journalism, I wouldn't exactly call TE uncontroversial. Not having a byline is very fundamentally different than writing under pseudonym.
How would you describe the difference as fundamental? Is it of who a reader has recourse to?
Separately, TE isn't exactly provocative or brave.