> If a journalist interviewed a popular camgirl who introduced herself as (say) LustyClaraXXX, and then "did research" to compare pictures, and revealed her legal name an occupation (say, a schoolteacher), would you consider it ethical?

It really depends on the context of the story, with additional nuances that a competent editor must consider:

Is this camgirl the central figure of this story?

What are her reasons for not revealing her real name?

You say she is a school teacher. What kind of teacher? Is she a well-known professor? Is she someone who teaches kindergarten?

Does she make more money from camming than being a teacher? That in itself could be another story about the system.

And on and on and on.