If employers really were desperate for workers, wages would rise. But wages haven’t risen. The only reasonable conclusion is that there isn’t really a shortage of workers.
Or too many businesses that are only viable if they’re paying less than what their employees need to live a stable lifestyle in their area (housing, food, transportation, health care)
Those businesses aren't sustainable then. A recent example given here was 24/7 gas station workers. The only reason they were working overnight was because wages have become cheap enough to capture the few overnight customers.
A higher wage means that the business is forced to have the employee on more productive work.