That was my point. Like TP, Jr, the term is loosely thrown around to represent Afro Cuban Son-based music. It's not being used in the technical sense.
I mightily disagree. Mambo is a subgenre of Son. Danzon IS Son. Another subgenre. The concept of Mambo does not begin within the 'Mambo' section of the danzon. It was used as a device to amplify the danzon, as a result of the popular dissemination of North American Jazz on Cuban soil. Or so said Antonio Arcaño, the late ensemble leader whose members included the Lopez brothers (Jesus & Israel). The first Mambo in the musical sense was reportedly by Bebo Valdes. Who led an orchestra. His band, like Arcano's tipica, was riffing off of Arsenio Rodriguez's conjunto. Who introduced the "Mambo" concept of the Son rhythm under multiple brass phrasing of repetitive notes over and over, that highlighted individual improvisation. There was nothing technically or conceptually related to Mambo in the history of the danzon until 1938, when Arcaño y sus Maravillas extended the danzon with the 'Mambo' section. Becoming more progressive and allowing for instrumental improvisation. The same exact phenomena emerged earlier within the bolero-Son. Where, like the danzon, a bolero was interpreted at a certain tempo and, eventually, became more progressive (sped up). While that isn't part of the popular narrative (re:bolero son), recording examples demonstrate it to precede the Mambo concept within the danzon.
That's your opinion but I don't see how you substantiate Mambo & Cha-Cha-Cha as being quite similar. In what way?
With the exception of "Guaracha," all Afro-Cuban genres are of the same expressive phenomena as they don't all have lyrical content, or don't have to, in order for them to be interpreted as such.
So did many others preceding El Benny. Like Miguelito Valdes, Orlando "Cascarita" Guerra, Frank "Machito" Grillo, and others. Benny More continued that tradition. He was no innovator. But he stood out talent-wise.
One individual or entity that escapes the Mambo origins conversation is pianist/arranger Rene Hernandez. Listen to his arrangements in the early 1940s, specifically for the Julio Cuevas orchestra. It's quite literally the same sound as Damaso Perez Prado's later work in the late 1940s.