I've found that when pretty much any woman, whatever her age, whatever she looks like, comes out as a domme, men come crawling out of the woodwork after her. I'm not surprised to find that its not much different for the pros.
People are attracted to powerful women. It's part of the human psyche. And I think it's true even for those of us who are naturally dominant -- some of my favourite people on this Board are dominant women (Netzach included). Does anyone else miss Eb?
So I guess it doesn't suprise me in the least that a 75 year old Pro Dominatrix finds no shortage of customers. The oldest I've run into personally would have been in her early 50s, although she was only semi-professional.