> I think the only way the economy improves is if older unskilled workers eventually leave the job market and make way for younger more technologically savvy employees.

I'm not sure I follow you here. In general, older employees are more skilled, even in technological areas. It's true that younger people skew towards tech, but you'll find few 20 year-old googlers with the skills of an average 40 year-old googler.

As someone with experience hiring people, I'd say that the main advantage in hiring younger people are lower salary expectations, possibly more idealism, and a small chance at them developing into a talent and while still staying loyal to the company.