Is ageism still prevalent in todays modern society? Are Older Women treated equally as Older Men? Why is the media offended about Older Women like Demi Moore dating Younger Men. Yet Hugh Hefner has sex with multiple women that are 60 years younger

You say that your question is about ageism -- but all three of your examples/follow-up questions are about sexism.

Is there ageism? Yep.

Is there sexism? Yep.

If we're ever going to figure either one of them out, it's important not to confuse the two.

Yes ageism is prevalent, Ive been a victim of it in the UK.
As for the old gender bias, no answer to that really, thats the way it is, way its will probably always be. Men are studs if they sleep around, women are tarts if they do it. Typical patriarchal society that objectifies women and the like...etc...

It is acceptable for an older man to pay for sex. It is more of a give and take type of thing. An old guy like Hefner wants something that looks nice on his arm.

Men have made the rules, and women who are suffering from the lack of choice of eligible older men are breaking the rules.

An older woman with a younger man, is more natural when it comes to body chemistry, and people hate on what is natural. Traditionally a woman's place is to nurture children, but when a woman gets older and the kids are old enough to take care of themselves,it is time to get the freak on, especially when you do not have a more permanent partner.

No older women are not treated equally. I am 51 and and when I was dating a 37 year old people were shocked.
If a 51 year old man dated a 37 year old womwn no-one would care.
Men who date younger women are studs but women who date younger men are sick old ladies or sluts.

Just think about the general prohibition against women telling their true ages as they get older. Most women will not disclose their true ages.

Think also about how older women who do something unusual, such as fight off an attacker, or break through the employment glass ceiling, are often described in the news as a grandmother, e.g. "Ann Smith, a 58 yr. old grandmother, took on her assailant and saved her wallet and her life." Or, "Jessica Jones, a 60 year old woman with four grandchildren, became the first female yesterday to take over the Tonight Show as host." Imagine them describing men the same age and doing the same kinds of things as grandfathers.

Of course, the reality is that all young people, male and female alike, will (with God's grace) grow old and eventually find themselves, like us, dismissed or rendered invisible by the youth who follow behind them.