Oh, and I am convinced that anyone who wants to continue teaching is required to teach what the students want to learn, regardless of country of origin.
Yes, especially if the teaching is for commercial reasons.
That's equally true in Buenos Aires as it is Worldwide.
That's why tango as a social dance isn't taught much.
What the dance needs (as opposed to what teacher needs)
are people who teach social dance for the pleasure of the dance,
not for the satisfaction of teaching nor the imperative of earning a living.