Assuming you live in a democracy, then yes, we have decided and do still decide. We can change the laws at any time (I know this is idealistic in a lot of countries) and use a new definition, or we can determine on a jury that something is or is not punished. I’m not comparing slavery to animal husbandry, but the US (I assume other slaveholding countries were similar, but I don’t know) has changed the definition to include or exclude slaves at various points. Murder is a social concept, not an immutable truth about the world.
Assuming you live in a democracy, then yes, we have decided and do still decide. We can change the laws at any time (I know this is idealistic in a lot of countries) and use a new definition, or we can determine on a jury that something is or is not punished. I’m not comparing slavery to animal husbandry, but the US (I assume other slaveholding countries were similar, but I don’t know) has changed the definition to include or exclude slaves at various points. Murder is a social concept, not an immutable truth about the world.