Identifying bounded contexts is a critical part of organizing extremely complex systems. You might have a Customer model that supports all contexts of usage, but in a certain bounded context you could know that only certain things from that type are applicable. There are a lot of ways to model this explicitly, but sometimes just having a clear document that expresses what these contexts are and what is involved in each is sufficient.

This also alludes to the benefits around separating your functions from your data. If your domain model is just data and the functions live elsewhere (i.e. within a separate abstraction representing each bounded context), then you have tremendous amounts of flexibility with how the system is composed on top of the model.