Final answer:
The primary concern with fewer workers supporting the baby boomer generation upon retirement is a Potential Pension Shortfall due to financial pressure on pension and retirement systems.
Step-by-step explanation:
The primary concern associated with the scenario where the "baby bust" generation does not have enough workers to contribute promised benefits to the retiring "baby boomers" is a Potential Pension Shortfall. The situation arises due to the increase in the number of retirees compared to the number of active workers, leading to financial strain on pension systems and other retirement-related benefits.
With baby boomers, comprising approximately 74 million people, entering retirement age, there is increasing pressure on the workforce to sustain pension funds, Social Security, and Medicare. This disproportionate ratio may lead to a pension shortfall as fewer workers contribute to retirement funds for a larger retired population. Additionally, advances in healthcare and life-extending technologies contribute to longer lifespans, thereby increasing the demand for sustained pension and healthcare funding.