I'm not sure what you mean by "Those in power" there are lot's of people who know, but recognise that he has chosen anonymity and see no value in putting a name to the person.

It's not so much a secret as it is simply not public.

Not sure what you mean by "not public", given that you can just search it up and find a Reuters article from March giving out his full name and background.

Simple logic, if you make an anti-nationalist-war point and current mainstream politicians are against the war, you are just an establishment stooge.