A major problem with doing data transformation in statically typed languages is that its easy to introduce issues during serialization and deserialization. If you have an object

  [{
    name:”ex obj”
    value:”a sample value”
    extraProperty:”I’m important”
  }]

And the code

  class myDTO{
    string name;
    string value;
  }

  var myObjs= DerserializeFromFile<myDTO>(filepath)
  SerializeToFile(myObjs, filePath2)
  

filepath2 would end up with without the extraProperty field.

You can also write code like

  function PrintFullname(person) {
    WriteLine(person.FirstName + “ “ + person.LastName)
  }

And it will just work so long as the object has those properties. In a statically typed language, you’d have to have a version for each object type or be sure to have a thoughtful common interface between them, which is hard.

All that bring said, I generally prefer type safe static languages because that type system has saved my bacon on numerous occasions (it’s great at telling me I just changed something I use elsewhere).