The reason that old women exploring their sexuality in a myriad of ways -- wearing lingerie probably being the tamest and most predictable way -- is considered offensive is that it reminds men that women change after menopause, that heterosexual sex changes after menopause. Once women don't have to think about pregnancy or birth control, sex is reborn, reckless and multifarious. And, natch, deeply threatening to men and male power. Anything that the binary,sexually repressed, pornographic (i.e. using sex as a means of social control)culture wants to say about women goes out the window. And we just get to be ourselves.