For a statically-compiled language, runtime reflection is probably a violation of the zero-cost overhead principle. There is a limited amount of reflection that can be done cheaply that has some value: getting the address of the vtable of an object [assuming it has one] for uniqueness, or getting function pointer identities for generic invokable objects.

Given compile-time reflection, providing standard library functionality for certain runtime reflection tasks (such as providing a list of field information for a struct/class/union, or listing function arguments) could be useful. On the other hand, it could end up being a locale-like scenario where it's either overkill or too weak for your use case, never in the middle.