By the way, Vlang (https://github.com/vlang/v/blob/master/doc/docs.md), uses "?" as well with error handling. To include it had/has a number of Go wishlist features.

The nature and culture of Go makes it harder to change direction and be as amenable, but the merits of such conservatism is a "depends" type of thing and can mean incorporating things many years after it has become fashionable or accepted.