Because people in your parents' generation had it easy. The post-WWII boom allowed even those without college degrees to find well-paying jobs, keep and advance

Because people in your parents' generation had it easy. The post-WWII boom allowed even those without college degrees to find well-paying jobs, keep and advance in those jobs for decades without having to job-hop every few years just for a meager raise, and retire with nice pensions. The situation is very different today.