[ocamoss]

Requiring the annotations on empty containers is the only way to have type safety if the type checker cannot infer the type of the container, like Pyright.

If the type checker can infer a type then the annotation would only be required if the inferred type doesn't match the user's intent, which means one would need to add fewer annotations to an arbitrary working-but-unannotated program to satisfy the type checker.

[IshKebab]

Yes but also having more complicated type inference makes the actual type checking less useful as a check. You see that in languages with global type inference too.

Adding explicit types strategically (e.g. in function signatures) tells the compiler (and readers) explicitly what the type should be, so if you add code that violates that it gives you an error instead of silently inferring a different type.