Have you considered a career as a kidnapper? Taking it a bit too far but think about the why. The code is proprietary regardless.
If culture is to be preserved I'm sure some of the original developers would make so. On the other hand, we could definitely do with shorter IP rights like 20-30 years, so that devs could legally release it within their lifetimes.
The tomb and its contents are the property of the Pharaoh in it.