That’s because one is considered “unvaccinated” until two weeks after the last jab. So if you get sick (and/or die) before the two week mark you are considered “unvaccinated.” Pressure to get the vaccine is not about the virus....
There are many getting the Delta variant who have been vaccinated for a long time. Look at the surge in Israel where they got almost everyone vaccinated. The surge is among those already vaccinated, thus the new push for a 3rd booster jab.