Except the costs of using types are usually in the form of a learning curve: i.e. when you are learning the type system it's relatively expensive, but once you'

Except the costs of using types are usually in the form of a learning curve: i.e. when you are learning the type system it's relatively expensive, but once you've mastered it it's just part of your coding practice. When you do run into the rare issue, it's usually east to solve it. By contrast, dynamic typing problems never go away. They're usually because of a faulty assumption, or due to a typo, or they're the cumulative hours you spend trying to figure out what exactly has to be passed into a function since it's not explicitly part of the signature, and the maintainer of the library you're using didn't document it well. In the long term, static typing is much less expensive, and it's not accident that people tend to prefer more types over the course of their career rather than less types.