The scare quotes around "fully" are unnecessary. Two doses is enough to drive down hospitalization risk to flu levels. Boosters aren't necessary from a public health perspective because boosting the already vaccinated has a miniscule effect on total hospitalizations. (Sure, if you want them to reduce your own risk, that's fine because they have been approved. If you want them to reduce disruptions in your workplace, that is also fine. Just don't expect to materially impact health system availability.) Vaccinating the unvaccinated has a much larger effect. Alternatively, Omicron seems like it will reach them before mandates take effect or Paxlovid supply is ready, with worse outcomes on the health system.