C++ has barely any feature complete compiler implementations and build systems aren’t ready for all of its additions, either (CMake and modules in particular). libstdc++ and libc++, gcc and clang are all not ready for production use or rather untested and/or buggy.
Unless you’re targeting MSBuild Visual Studio Solutions and Windows only, C++17 is currently the most up to date, stable, and battle-proven version.
It's a shame "C with classes", as C++ originally was, didn't stick around for parallel development.
I work with C daily and I'm well aware of its many shortcomings (e.g. its huge list of undefined behavior and its PDP11-centric view of modern architectures), but with some effort I believe it could function as a semi-portable second-level intermediate representation. Nim uses it as such, IIRC.
Compiling to C first would introduce some of its own issues, for sure, but I imagine doing so would alleviate the pressure the C++ standards committee puts on compiler vendors each time they expand the size of the kitchen sink.
