Interesting points.
Contrary to what people often say over on the Oldies and Standards sections of this website, there are many advertisers who are targeting older consumers. They just don't buy radio much. But they do buy oldies TV and they buy cable and network news/talk.
Not all media buys are completely computerized and rational. Some advertisers buy what they like and what they (and all their friends) agree with.
Historically, younger people haven't paid much attention to current events or voted as much as their grandparents. Baby boomers were an exception. The draft can do that to young people. But no, everybody of any age tends to hang with people who agree with them and with whom they share interests and values. And people, of any age, turn to media for confirmation - not information.
makers of adult diapers and laxatives need to advertise somewhere