I get that the ingots need a certain draft angle in order to easily eject from the die, but why is the angle usually so extreme? The ingots are, from what i believe, just used for easy storage of metal, but why wouldn’t a lesser angle then be favorable, as the packing of the ingots would be more efficient?
It’s the draft angle for the casting. You make the hole you’re later going to pour metal into by pressing an ingot-shaped piece of wood or steel into specially-formulated sand. When you pull it out, you don’t want the sides to stick to it or collapse into the ingot-well. If they do, you have to do the whole step over again.
Having a generous draft angle ensures that the casting process goes smoothly, and densely packing the ingots for storage is a non-issue. Even a loosely piled stack of aluminum (read: lightweight for metals) is so heavy that you have to think carefully about whether the floor can support its weight.
You can alternate their orientation in a pattern such as
Edit: [found an image](https://cdn.thepipingmart.com/wp-content/uploads/2023/01/What-is-an-Aluminium-Ingot-and-What-are-Its-Uses.png).
Then the wasted space is very small regardless of incline. I am also not sure if space efficiency even matters that much for metals, they are pretty dense after all.