The article which you clearly didn’t read specifically states:
My analysis had to be entirely based on the profiles themselves, not the credit card data. There is no such thing as a “paid account” for women because women don’t have to pay for anything on Ashley Madison. As a result, I couldn’t use “paid account” as a proxy for “real,” the way analysts have done with the male data.
Edit:
In fairness, @beschizza does indeed say
So if that’s what you were referring to, I apologise.