C++20 has modules, which replace header files completely (unless you use old libraries which aren't available as modules yet). Compiler support is there, but unfortunately IDEs are lagging. If you use modules with Visual Studio, say goodbye to IntelliSense. Maybe they'll iron out the bugs in a couple years...
They needed the most powerful, most flexible module system ever, so it might take decades to really become useable. Adoption has been painfully slow so far, it's insane complexity really doesn't help.
You can use modules to structure your own codebase. No more need to write headers and think about how to structure your code in terms of compilation units. But yeah, your link shows that practically none of the popular libraries (except STL) can be imported as modules today.
