"Is it age discrimination?"
Yes and no. Ads "tack up" what sells. The media seldom glamorizes aging women, but they do put aging men on a pedestal. I suppose we know who mans the media mostly! A man with a thousand wrinkles, even creases, baggy eyes, reumy eyes, and drooly lips is considered a fine, sexy catch, especially if he has money and can give women great lives. Prostitution takes on many faces.
If more women would get wealthy and offer men the bigger bucks, they just might start stepping up on the gorgeous stage. We hear about older women being scammed by fortune hunters who marry them and walk away with their life savings. Women need to protect their money so these men can only get a few thousand at a time. That way they can keep them indefinitely. Let's face it, people with money can pay for what they want even if it is fake. Many older women are being taken now and do not know it. I imagine some do not want to know it!
Ordinarily, women over 40 are not considered attractive, and men are bamboozled by many women under 40 who are trading their youth and beauty for comfort. That practice is as old as man. Men get what they want when women are weak and in need. Men who creep to ugly or needy women know that they are vulnerable.
The cost of living is rising and wages are not catching up on most jobs. Ages ago, when jobs were mostly for men, and women's place was in the home, in some cultures, men could marry as many wives as they could afford. Even in monogamous cultures, men had women outside of their marriages, and many turned a deaf ear and concluded: "Men will be men." Even wives pretended that they did not know it. Some late bloomers do it now. Everything that happens in society affects ways of life in many capacities.
Once upon a time when more men respected their aging wives, they (the women) were more useful to them. They worked harder than young women, and they were wiser and useful in struggling families. They gave them many children to help out on the farm or work elsewhere to earn money for the family. Older women have stronger backbones and are more resourceful. Now, that men have more wealth, they feel that they can "play." Many kick their aging wives aside and get someone as young as, or younger than, their own daughters. Human beings do not always use wisdom but live life as it is dealt to them.