That was something that occurred to me reading the latest NYT article. I don't personally know any massage therapists, but I would imagine the vast majority of them absolutely hate the fact that people think "happy endings" are a normal thing, or that the work they do is in any way sexual. The fact that all these therapists are coming forward is almost an admission against interest on their part, because it does significant damage to their careers and the general image of their profession.
Also, as long as I'm pontificating on jobs that I have no direct knowledge of, my understanding of professional athletes and massages is that they typically find one therapist who knows them and their body well and stick with that person. The fact that
Watson
had 66 different therapists, all women, doesn't by itself prove anything, but it is hugely suggestive.