The part of this idea that felt valuable to me is really the simplification, removing the need to have to think about imports for lots of simple typing cases. I think this would be especially useful for newcomers to the language, or for someone starting to learn about type hints.
@srittau yes, I remember that sort of syntax was mentioned in the old typing-sig thread where the soft type keyword was first proposed. It’s a neat idea, and I think these two ideas could be compatible and complementary.