Of course that gross fatality rate is for a sample aged 16 - over 80, what the study doesn't show is deaths broken out by age group. You would expect to see a markedly different set of numbers for the 70+ cohort.
Even just splitting into 50+ and under is enough to see a huge different set of data.
https://assets.publishing.service.go...riefing_20.pdf
That document has a good data set in Table 5. But you must only compare within an age group, or you get weird outcomes.