You haven’t implemented an Anti Corruption Layer. What you have done is a function that validates input data, and this is not an ACL, I think there’s a misunderstanding.
An ACL relates to the data model itself. Imagine a system A that publishes a `PlayerStat` based on its own data model. If system B retrieves those events and wants to store them in its own DB, for instance, then you create a coupling between how you store data and the data model of system A. It can lead to some issues if at some point system A decides to change its model.
If you want to prevent that, you can use an ACL.
It means having system B manage its own model, but creating a thin layer to map how system A model a `PlayerStat` to how system B model a `PlayerStat`.