Hi, I mention in the article that "It is easier in general for a C++ user to use a C library than it is for a C user to use a C++ library." which is where the advice comes from.
I agree. But "wants" is a term indicating personal preference. I understand that C is best suited for maximum portability and performance. But as a C++ developer I prefer libraries that come with C++ interfaces (and you do mention that it is good to provide a C++ wrapper as well).
Thanks a lot for your feedback. I decided to remove that since I think you are right about indicating personal preference.
I do not want this article to be a list of preferences but rather an analysis of the considerations that popular C libraries make (eg: stb, sokol, etc) and that new authors should also reason about.
Because the binary interfaces generated by C libraries are simple and therefore universally supported. It's just normal symbols and calling conventions. Conforming to this ABI benefits users of every other language, not just C++.
C++ ABIs are rather complex and much harder to interface with. The existence of concepts like virtual functions and exceptions significantly complicates the implementation of foreign language interfaces.