I'm about to turn 60. My highly successful, and very handsome husband is 57 - we've been together for over 30 years and have a great relationship. I'm far from invisible - in fact, younger men notice me all the time, and it's not because I look like a movie star. Assuming that most middle-aged women are plump and carry around purse dogs is not only absurd, it's incredibly misogynistic. Many, many of them are vibrant, interesting, cool, fit, and sexy.
Lots of men are interested in how they can be "impressive" to other men, rather than in how they can have quality relationships. Not that there are no older guy/beautiful younger woman ones that are substantive, but your advice seems to be geared toward the former and not the later. I guess it all depends on what your priorities are.