Herb's CppFront looks like the best hope for a clean C++ future
CppFront is just like Carbon and Val, with a completly different syntax, translating to C++ is just an implementation detail, he just markets in a different way given his position at ISO, most likely not to raise too many waves.
Carbon is DOA as it hacks a compiler, and Circle isn't even in active development (again if it would compile to C++ that would be a better direction).
At the same time putting ideas from Carbon to CppFront is possible (I wish Carbon developers would also think about going the preprocessing direction).
CppFront is just like Carbon and Val, CppFront compiling to C++ is an implementation detail, C++ and Objective-C aren't C, just as CppFront isn't C++, regardless of the sales pitch.
It's not intended as a separate language.
According to wikipedia, Eiffel was created in 1986, making it a contemporary with C++'s initial development. From what I can tell, it's creator had no affiliation with the development of C/C++, and it was created for reasons completely unrelated to C++.
CppFront was created by the C++ committee chairman for the explicit goal of providing a path forward for C++. Herb explicitly stated that the inspiration for using C++ as a compilation target was taken from Bjarne's initial implementation of C++, which compiled to C.
The way Herb Sutter tries to sell Cppfront, versus all those other languages that have backends capable of generating C++, is exactly that, as ISO C++ chairman he is trying to portray Cppfront isn't like the others, given his position.
Hasn't as it is, he would use the same terms as the Carbon and Val folks.