When the labor market is severely disrupted, two age groups suffer in distinctive ways. Those who are just a few years from retirement, but then lose their jobs, are more likely to end up retiring earlier than expected. They lose several years of market earning and have to draw on their retirement savings during those years, which combine to reduce their standard of living during what may be several decades of retirement.
The other age group that especially suffers is young adults just entering the workforce for the first time. Those who already have well-established jobs may have ways to telecommute, or to be called back by previous employers, or at least to have a resume of past work when they are applying for a new job. Here's some US data showing that unemployment rates and labor force participation rates are consistently lower for those in the 20-24 age group than for the population as a whole.
The International Labour Organization describes some of these problems for young adults in an edition of ILO Monitor: COVID-19 and the world of work (May 27, 2020, Fourth edition). The ILO report notes (some boldface type omitted):
Young people constitute major victims of social and economic consequences of the pandemic, and there is a risk that they will be scarred throughout their working lives – leading to the emergence of a “lockdown generation”. ...
Both technical and vocational education and training (TVET) and on-the-job training are suffering massive disruption. In a recent ILO–UNESCO–World Bank joint survey, around 98 per cent of respondents reported a complete or partial closure of technical and vocational schools and training centres. Although over two-thirds of training is now being provided at distance, often online, few low-income countries have actually made that transition.
Another new global survey by the ILO and partners of the Global Initiative on Decent Jobs for Youth reveals that over one in six young people surveyed have stopped working since the onset of the COVID‑19 crisis. Among young people who have remained in employment, working hours have fallen by 23 per cent. Moreover, around half of young students report a likely delay in the completion of their current studies, while 10 per cent expect to be unable to complete them at all. On a standardized scale of mental well-being, more than half of the young people surveyed have become vulnerable to anxiety or depression since the start of the pandemic.
It's worth remembering that in much of the developing world including many nations of sub-Saharan Africa, the Middle East, south Asia, and Latin America, one of the biggest economic and social problems for the short-and the medium-term is how the economy can create sufficient jobs to absorb large numbers of young adults into the workforce. The pandemic and its economic aftershocks will make make it even harder to incorporate young adults into the labor force.