Huh? tests are there to make sure your code behaves correctly, e.g it works. Don't you do that in static land?

You write tests for things that actually matter ... like you know, testing functionality.

You don't waste time writing tests that simply check if all the arguments received the right type. This is taken care of by the type checker.

Besides, the biggest benefit of types is readability.

I don't see tests as you describe in dynamic languages much. E.G this is how you would test Rails controllers https://gitlab.com/gitlab-org/gitlab/-/blob/master/spec/cont... . I don't think its that different than java world.