This is an awful article. It is extremily rare to choose `struct` vs `class` because of their default visibility. It is much more usual because of style. Is it

This is an awful article. It is extremily rare to choose `struct` vs `class` because of their default visibility. It is much more usual because of style. Is it a functor? Is it a data structure? Do I need C-compatibility? Do I want to encapsulate behaviour and validate correctness? Do I want to maintain the company style?