If messages that are swapped contain data, I find that FP (functional programming), if implemented with type checking, can include as much or if not more boiler

If messages that are swapped contain data, I find that FP (functional programming), if implemented with type checking, can include as much or if not more boilerplate than OOP, where object methods implicitly access the data (object attributes). This may sometimes lead to code that is difficult to reason out... but if you have a few objects and many functions, OOP can be less verbose than FP. I say this as a stronger supporter of FP than OOP.