I'm guessing this is basic mathematical slight of hand, where the numerators are sharing the same denominators instead of restricting the data to the same sets.
A more accurate measure is to present the number of deaths per 100,000 of each group,
The age-standardised mortality rate for deaths involving COVID-19 is 32 times higher for unvaccinated people than for those who received the second dose (England) Office for National Statistics – Public Health Data Asset, National Immunisation Management Service
