Sure, Boost is full of metaprogramming insanity, but with today's C++ standard library it's not necessary to use Boost.
10 years ago template heavy code in C++ did suck, because we had slow compilers, dumb build systems, 7200 rpm HDDs and a need to use Boost to augment the bare bones standard library.
I'll be the first to admit that C++ has decades of cruft and design errors. But the metaprogramming works pretty well now. C++'s current problems are (IMO) weird undefined behavior, e.g. the distinction between POD and non-POD types; having both pointers and references, the ancient exception system, and in general a lack of tools for enforcing memory safety.