Theologically, why did Jesus have to die?

Or more formally for the acquainted, which theory of atonement makes the most sense to you?

The question of why the claimed messiah died is a question Christianity was forced to answer from the very beginning, and yet it’s also not a question where a firm dogma was established. The most popular answers to this in 900 CE aren’t the same as the most popular answers today.

Some of the options are listed here:

https://en.wikipedia.org/wiki/Salvation_in_Christianity

Two theories dominate today, and I admit I have questions and concerns about both of them.

For modern Protestants, Penal Substitution seems to have won the day. The idea is that God wanted to grant humans mercy, but that to satisfy his unchanging just nature, someone had to be punished. And so that was the innocent Jesus Christ, himself.

But this notion of justice for serious crimes, in which one person can volunteer to be punished in place of the person who actually committed the crime, is virtually unrecognizable to us. Advocates cannot make comparisons to how we deal with violent crimes. So instead, sin gets compared to things like traffic tickets or credit card debt.

For modern Catholics and Orthodox Christians, it looks like Christus Victor, a revision of ransom theory, is most popular. Here, Jesus’ death and resurrection was a demonstration for the world that God would always be victorious over death and evil.

But this raises countless follow-up questions. Demonstrated to who? What was it meant to convince people exactly? Did it do so successfully? What changed in the world because of this demonstration?

I don’t see the atonement theories question come up a whole lot in this subreddit, despite how central it is to Christianity, so I look forward to seeing people discuss.