Primordial Sex--Eden as Allegory

[Aegrus]

How is that not sexist? Is that the justice you would want for your daughter, sister, etc. if that were to happen to them? Does the fact that we put rapists in jail make man's law more moral and just than biblical law?

It certainly does.
But think about the life of the ancient israelites.
A woman who was not a virgin was surely out alone. No one would marry her. She'd be effectively cut off from social life.
The reason why this law was in effect was due to this fact. It's now obsolete, since understandings and viewpoints on things have changed.
But for it's time, the law was put forth to protect the woman who was raped.

If a man lies with a man as one lies with a woman, both of them have done the detestable. They must be put to death.

It's certainly no new law. Variations of it can be found virtually everywhere.

The most intelligent answer to this question that I've heard to date. The bar isn't high, but still, well done.

Here's where the argument fails. Instead of making the women marry their rapist, why doesn't the bible tell people not to ostracize women who were raped?

Because the people who wrote it were sexist bigots by today's standards, and their book reflects their views.