So is being male a proxy for height, or is height a proxy for being male?

yes to both

It's sad on an individual level, but not necessarily at the species level. If men are taking more risks than women but only to the degree that they still die on average in their elderly years, that means they are overall still remaining relevant in their sexually valuable years and sticking around long enough that they're likely to pass down some generational knowledge to grandchildren. Doesn't seem that bad to me considering how low life expectancy used to be.

When 900 years old you are, look as tall, you will not.