That’s not the issue. The issue is the borrow checker making things slower to write. Changing requirements isn’t just moving code back and forth, it’s changing the existing code, moving it around, adding new dependencies, using existing code in a new way, and so on. Not easy to do if the borrow checker is screaming at you about some moved ownership.
That’s what dynamically typed languages are good at: pass in a dict/object/hashmap/whatever with some attributes to test something out, pass that around, transform it, add keys/fields, extract parts of it, transform them and return those, etc., see that it’s working, and then you refactor it with proper typing, linting, and tests where a borrow checker is very very welcome.