Unit testing not only replaces the need for strong typing, it does so without any extra effort on top of what you'd already do for unit testing That's not true

Unit testing not only replaces the need for strong typing, it does so without any extra effort on top of what you'd already do for unit testing That's not true. I work on an e-commerce system. Ensuring that people don't accidentally use Floats where they shouldn't requires quite a bit of additional effort which could be avoided with a type system.