Looking at the source, this was about King County, Washington, where more people over age 65 have completed the full vaccination series than there are census-estimated residents of that age. Effectively everyone over 65 has been fully vaccinated there. https://kingcounty.gov/depts/health/covid-19/data/vaccinatio...

If you tally up more age categories, about 92% of people over the age of 35 have been fully vaccinated.

Or flipped around, 80% of unvaccinated people in that county are under the age of 35, 15% are age 35–50, 5% are age 50–65, and essentially none are older than that.

It is amazing that even so, 83% of hospitalizations and 75% of deaths were among the unvaccinated. These vaccines are astonishingly effective!