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First of all, 50's is a common way of abbreviating the decade. It kind of bugs me for the reason you mentioned, but it's not wrong.
Now, I might be crazy, but I kind of want to defend the point I think he is trying to make. I think he is trying to point out the irony that men (including himself) would like to have more opportunities to have sex, but that it is difficult to meet women and be successful in getting them into bed. In his mind, however, a moderately good-looking woman, if she were so inclined, could walk into a bar and find probably multiple men ready and willing to sleep with her. So, it is frustrating that women have plenty of chances to get laid but don't take them, while men would love to have the chance but it doesn't come along as often.
A male friend of mine has made the same point to me-- he's a relatively good looking man with a nice personality, but he estimates that his success rate in getting a woman to go out with him (I'm not talking about sex here) is maybe 1 in 10. Then, you go out, and maybe the date goes well and maybe it doesn't, maybe you go out again and maybe you don't, maybe you eventually end up sleeping with the woman, maybe you don't. Whereas, he says (and I think he's right) that I could go to a bar and find someone to go home with that night if I felt like I needed to get laid. But, it's something that I wouldn't do unless I was seriously, seriously sex deprived, and so from his point of view, there's all this wasted opportunity that he wishes he had.
Whether this has to do with differing sex drives in men and women at different stages in their lives, or is culturally conditioned, or whatever, it must be kind of frustrating from the point of view of a man who hasn't been laid in a while.
Although, men, I have to say, seeming kind of desperate to have sex isn't going to win you point with most women I know.