Annotating empty collections is one of the few places you need to annotate outside function signatures. It's not a big deal. It doesn't happen that often.
things: set[tuple[str, str, int]] = set()
users: list[User] = []
In fact, I recently migrated a project from Pyright to Pyrefly for performance reasons, and there was very little I had to change between. The most annoying thing was Pyrefly's lack of exhaustive pattern matching for StrEnum and Literal[...]
> To improve type safety in these situations, type checkers that infer Any for empty containers can choose to generate extra type errors that warn the user about the insertion of an Any type. While this can reduce false negatives, it burdens developers by forcing them to explicitly annotate every empty container in order to silence the warnings.
ie: "type checkers that don't infer container types can emit an error and require users to annotate"