It seems the C++20 standard library concepts missed out on some
requirements for one concept to subsume another. For example, should we
consider it incorrect that concept std::integral is not subsumed by
std::destructible, std::copy_constructible, std::regular, etc.? If T is a
fundamental integer type, then T is regular, but conforming compilers can't
use these facts in partial ordering of templates. Should this be a Defect
Report? Or has this sort of issue been considered by the Committees, or is
anyone working on a related paper?

-- Andrew Schepler