Is American turnover in Congress actually that fast enough for this to happen? We have more people over 40 than younger people and the influx of youth is being

Is American turnover in Congress actually that fast enough for this to happen? We have more people over 40 than younger people and the influx of youth is being floated by an immigration policy that favors middle- and upper-class, basically the brain drain, of the rest of the world (read: people interested in business-friendly policy, etc), and older people, say, everyone 40 - 60, will have even greater life expectancy, so those who are in power may be in power when current teens are adults, just as Nancy Pelosi has been a Congresswoman my entire life and a good chunk of my mother's.