For example, men live on average 5 years less than women. How should we fix this? Massive government expenditure into men's health research and men's occupational safety?
Would that be a bad thing? There are a lot of other negative mortality outcomes linked to demographics so maybe we take a look at those as well. The link between abortion bans and mortality rates for women seems pretty germane in the US at the moment…
Maybe, but if the goal is shrinking the gender lifespan gap, reducing women's mortality would actually make the gap worse. You should focus on reducing men's mortality first, until the gap disappears or reverses, at which point you can start considering women's mortality again.