> There is nothing about types that would make incremental develpment harder.

Oh, please, this is either lack of imagination or lack of effort to think. You've never wanted to test a subset of a library halfway through a refactor?

Yes, type checkers are very good at tracking refactoring progress. If it turns out that you can proceed to test some subset, then congratulations, you found a new submodule.

I am continually astounded by the stubborn incuriosity of humans with a bone to pick.

What in the world are you talking about. Please specify how lack of types helped you in your aforementioned scenario.

I don't think it's a lack of curiosity from others. But it's more like fundamental lack of knowledge from you. Let's hear it. What is it are you actually talking about? Testing a subset of a library halfway though a refactor? How does a lack of types help with that?