Perhaps there's a future where "add a new feature" means "add tests for that feature and re-implement the whole project from scratch in AI". But that approach

Perhaps there's a future where "add a new feature" means "add tests for that feature and re-implement the whole project from scratch in AI". But that approach would create significant instability. You can't write tests that will cover every possible edge case. That's why good thinking & coding, not good tests, is the foundation of good software.