Do you have the link? Because we can't tell from those figures what the relative mortality rates are. It might be that some of the age and sex differences reflect differences in becoming infected. In fact, several studies, including the Diamond Princess, where we have the most reliable numbers, suggest that older people are more likely to become infected. So the higher death total would partly be a result of that, rather than just a higher rate of deaths/infections.
The size of the groups also matters. E.g., the number of 70-79 who died is about the same as the number of 80-89, but that's presumably because there are I would guess roughly twice as many people in the former group as the latter. Even more so wrt 90+.
Another thing to keep in mind is that any data from Italy are very incomplete, i.e., the vast majority of cases are not yet closed. This could affect results, e.g., older people likely die faster after infection than younger people, so a disproportionate number of deaths of younger people probably haven't been recorded.