>Historically, the rationale for excluding women from the draft was that they weren't eligible to serve in combat roles, voluntarily or otherwise
Historically countries didn't let women fight in wars because they didn't want their civilisation to die out. If a country loses a double-digit percent of its men it can still repopulate just as quickly, because one man can make multiple women pregnant, while if it loses its women then it takes significantly longer to repopulate, because one woman can't have multiple babies at the same time so the birthrate will necessarily be reduced.
Historically countries didn't let women fight in wars because they didn't want their civilisation to die out. If a country loses a double-digit percent of its men it can still repopulate just as quickly, because one man can make multiple women pregnant, while if it loses its women then it takes significantly longer to repopulate, because one woman can't have multiple babies at the same time so the birthrate will necessarily be reduced.