WG14 has only "worked" fairly well insofar as it did absolutely nothing but file the serial numbers off of things standardized in C++ and release them. The biggest C-original features (type generic macros, annex K) are all gigantic boondoggles. Even many of the features that were lifted from C++ were poorly thought out (e.g. compatibility between <stdatomic.h> and <atomic>).
The biggest C-original feature since C89 is easily designated-initialization in C99, and WG21 couldn't even get that simple thing right when they tried to copy it into C++20 two decades later (even though Clang had a working implementation in C++ mode since forever which just had to be copied by the standard).