I agree with most of what you wrote. Mainly, anybody that doesn't know and appreciate on1 vs on2 must not follow the dance scene that avidly. And yes, though there are some great dancers in Europe, most are Latinos from the US or the Caribbean. Juan Matos lives in Milan. But he is originally Dominican. Adolfo Indacochea also lives in Europe, but is from NY (and I believe Puerto Rican). Caribbean Latinos (mostly Cuban or Puerto-Rican) are generally the top dancers. But obviously, people of any background can excel if they work and study.
However, I disagree with your reason for on2 being the preference of top dancers today. The main reason is musicality. Dancing on2 is much more in tune with the percussion in Afro-Latin Musica. Nuyorican Eddie Torres is credited with being the founder of the on2/mambo/NY style. Eddie has said that, many years ago, he wanted to perform for Tito Puente's live performances. Eddie was at that time a "street-taught" on1 dancer. Tito told him that if he wanted to perform for him, he had to dance on 2. Julliard-trained Puente's reasoning was that breaking on the 2 was much more in sync with the percussion of his music. And percussion is the "heart" of Afro-Latin Music.
Anyone that is truly interested in the genre should learn to play some percussion. Once you experience playing the Congas, Clave, y timbales, you will likely come to appreciate dancing on2 that much more.