The Baby Boomers are retiring. That is going to push down overall labor participation rates. So that really is not the bad sign you claim.
What is a bad sign is pre-Covid falling life expectancies. That does not happen in a healthy country. It is almost entirely correlated with trump voters. It also involves dropping workforce participation among people who are not in education or retired.
Darwin is killing those who do not believe in evolution.
Those who believe in science, health and education are advancing as a species.