Post-pandemic, economists have estimated that millions of workers have left the workforce and have yet to return. The exact size of this gap in the workforce is not known, and it poses interesting questions given the lowest jobless rate in decades in the US. However, the labor force participation rate has remained lower than pre-pandemic levels and it has been found that higher death rates in recent years, partly due to the pandemic, have shrunk the workforce overall. Additionally, immigration slowed during the pandemic which also may be contributing to the worker shortage.
See "Post-pandemic, US workforce participation remains lower than before for various reasons", Michael Sasso, Bloomberg, February 24, 2023