The sync.Map.Range, filepath.Walk and other similar functions with visitor pattern in standard Go packages will remain there forever because of backwards compatibility. This means that new functions must be added to standard Go packages in order to be able to use them with iterators starting from Go 1.23. This complicates Go without reasonable benefit:

- You need to be able maintaining code with multiple ways to iterate over various collections in standard Go packages.

- You need to spend time on deciding which approach for iteration to use when you write new code.