Earlier quoted context omitted.
Some things never change, regardless of the modern C++ discussions. Apple, Google and Microsoft "modern C++" frameworks also use their own types, instead of the standard library. See Android NDK, IO Kit / Driver Kit / Metal bindings, C++/WinRT and WIL.
IOKit dates to circa 1999; it’s not “modern C++” by any reasonable definition.
Let alone those that aren't neither WG21 members, nor C++ compiler vendors.