I think you misred my comment and think I think exactly the opposite from what I wrote. To reiterate my point: whether OOP or FP you still need to invest time

I think you misred my comment and think I think exactly the opposite from what I wrote. To reiterate my point: whether OOP or FP you still need to invest time researching, understanding and writing down domain model and designing your application. And if you don't, the problem doesn't go away and instead hides in some form of technical debt.