If women started working in dangerous environments that harms their bodies, it would have a direct impact on their reproductive ability..which on a large scale would be detrimental to the perpetuation of humans as a species and hence our survival. This is how we evolved. Not likely going to be a popular opinion, but it is mine.

Also remember lot (most) of Marxism predates Darwin and evolutionary biology. Even though Darwin and Marx were contemporaries. Since left is still quite based on Marxists ideas, it just does not account for many evolutionary biology theories and hence tends to find reasons which do not explain things correctly.

I would take it one step further. Marxists/Leftists generally discount time as a variable entirely. It's all about addressing a concerns in the present. There's very little to no considering to the impact of time. There are two ways this disregard of time manifests itself. First, is what you mentioned, in that there is no consideration for the value of wealth building, which (1) takes time and effort, and (2) produces the greatest returns over multiple generations (Basically, every one of us are standing on the shoulders of our ancestors). The second is preference for distributing the fruits of labor in the present equitably instead of using the fruits of labor to create greater returns in the future.

While not specifically about time, the difference principle in Rawl's Original Position is also relevant. Under that principle, inequality is permissible if it can lead to the worst off being better off than they would if there were equality. This principles presupposes that time is considered when trying to maximize well being for the worst off. If you want to maximize the well being of the worst off in the present, you implement equality right now, but that may be worse for the worst off in the future.

This is a tangent, but,

"More Americans died in making stuff for the WW1 than in the actual war, as the conditions of factory work was brutal."

I'm doubtful that this is true for many other countries involved in that war.

Factory work was not yet as common place as America and England in many other countries. Ford assembly lines were not yet widely used when WW1 broke out, most of the WW1 was fought with less industrialized weaponry.

That's partly it, but what I really meant was that America didn't have many combat casualties, relative to other countries. 53,400 according to Wikipedia, which was less than Canada's 56,600, and much less than France's 1,150,000 or Germany's 1,800,000.

The US basically wasn't a major combatant in that war, so it's not a representative country to use as an example. I'm sure it does show that factory conditions were brutal, but it falsely implies that they were more brutal than combat conditions.