No mystery here. This virus came and changed everything. Employers have not advanced with the times.
Boomers are retiring rather than deal with the high possibility of getting infected. They took their experience with them. The younger generations are now filling those spots. Only there is not as many replacements as the boomers that retired.
So workers now have a choice of where to work at. They can pick and choose their employers because of that gap between the amount of workers and the jobs available. Employers are still thinking they can pay minimum wage and limit hours to less than 40 hours a week so they don't have to supply benefits. Those that don't step up and are still thinking they can get away with low pay are the ones not getting employees.
In addition, the women in the work force who have children, do not have support and have to stay home to take care of the kids. Bus drivers are lacking so many have to go twice a day, to take the kids to school and to bring them home. Kindergarden places aren't handling enough kids, those that are open, and they are charging record fees. Momma has to prepare food, do laundry, and all the things necessary to run a house hold. Many parents are deathly afraid of public schools and believe with good reason that their children could be infected and bring it home, so they are home schooling that takes time and personal attention.
The younger generations have been taught that the dollar is everything. They don't have job security because first time workers are to be laid off, it's them. They've learned there is no loyalty to the job, only to the dollar and they now have learned that lesson well. They will not work for peanuts and many demand working from home. If the employer will not meet the demands of the workers, they will go else where to someone that will.
Again, no mystery why workers are not showing up. Just employers that don't want to pay what is needed to get them.