"Or because women don't wear corsets anymore and seldom have hired help, therefore marriage shouldn't be restricted to one man and one woman.
Make sense to you? (Scratches head....) "
I think the author was saying gender has become less relevant in modern of marriage. We have the freedom to change 'roles'. You have 'house husbands'. You have women who are the breadwinners of the house, etc. In essence he's saying that the roles of husband/wife with the man and woman in a marriage have become negotiable and flexible. Therefore, since either man or woman can assume the role of 'wife' or 'husband', why not have two men or two women assuming these roles? I think this might make perfect sense....if this were the theater. (After all, men played to roles of women during Shakespeare's time.)
I got his point, and you elucidated it further. I was reducing it to absurdity! Might as well say that because children can now get engendered without actual sexual congress, no need for marriage at all for procreation.
Obviously the author is too smart for his own good. When someone has too much admiration for their own brain power and not enough for simple common sense, along with rejection of all tradition moral absolutes, you get - Voila!
Handbasket time, moving in a southerly direction.