There are also (at least) two relevant followups to this paper:

Response to “Fibers under the magnifying glass”: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p086...

Response to response to "Fibers under the magnifying glass": http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p152...