It could only be approved on the basis that the pandemic imposed special conditions that required everyone to get vaccinated. OSHA probably could do something on facilities that they own or lease. The jurisdiction for the requirements or safety regulation notices would lie with the states, and the federal government would have to allow the states to enforce them on federal property.

The large companies wanted legal cover since many of them are imposing return to office guidelines that require vaccinate or test. The absenteeism caused by people or their kids being out sick is a big drag on the economy. Seeing huge decline in travel which is feeding into inflation in things people divert spending to the home.