At least part is worker shortages. Any unemployment less than 5% is generally considered full employment. We are at 3.7% even with concerns of the economy possibly going into a recession, so more jobs than works to fill them. Couple of reasons unemployment is so low.

• Total covid deaths in the US is pass 1.2 million, adding excess deaths pushes that significantly higher. Including disability from covid means a lot of people not in the workforce anymore.
• US average population age is going up, which means the ratio of workers to retired is likely increasing, putting further pressure on finding more workers.
• US has a long history of worker exploitation. Current unemployment makes that harder along with more people being work from home. At least some business "leaders" are pushing to change that anyway they can (back to office, employing kids, doing silent layoffs, etc.)

Employment pool can be expanded, or workers can be more efficient to do more with less time. Certain states want to expand the employment pool and the easiest way is to make it so kids can work more. I can think of no real reasons this is a good thing and is actually a net positive. "allow(a) young adults to devleop their skills in the workforce." is not one of them, and is more likely code to try to get new workers to be like old workers pre-pandemic.