If men generally stay younger for longer than women, why is the global average life expectancy for females more than males?

I don't think men generally stay younger for longer than women (I assume you mean "younger looking.")

I think rather, at least in western cultures, society has regarded men as still being attractive at an older age than it has regarded women of the same age. But I also think that attitude is changing.

Large parts of the world are still at war, which are primarily fought by young men. The general consensus is that war is pretty bad for your health if you’re fighting in one.

Men only have one X chromosome, which increases our risk of expressing defective recessive genes. Also, we love smoking.

Because women are jealous of our youthfulness.