the flip side of this is it makes it immensely difficult to build source/documentation tooling for swift (compare with languages like java where the tooling is far ahead of ours). we also have a problem with so-called “dark API” that’s completely un-documentable and un-indexable (see explanation here), and i’m not sure if there exists any parallel to that problem in any other language.
it’s possible that this is one of the factors that has slowed uptake of the swift language among large organizations.