[leafboi]

From a purely structural standpoint there is no risk. But you are talking about something different. You use the word "confusion."

Confusion is an organizational issue that can be handled with social solutions like names, namespaces and things like that. You can compose functions to form higher order functions with proper naming to make sense of things. So for example if you have 30 primitive functions you can compose smaller components into 10 bigger functions in a higher layer and expose that as an api. This is more of a semantical thing as you can still use the lower level primitives as a library and chain those lower level functions to achieve the same goal as using the higher level api, the higher level functions just make it easier to reason about the complexity.

Confusion, Semantics and organization is in a sense a social issue that is solved by social solutions like proper naming, grouping and composing. I'm not dismissing these issues (they are important) but I'm saying they are in a different category.

Overall though the problem I am addressing is structural. There are real structural issues that occur if your functions are not pure. When 4 methods operate on shared state in a class all four methods become glued together. You cannot decompose or recompose these functions ever. They cannot be reused without instantiating all the baggage that comes with the class.