I wouldn't say so, C isn't complicated as a language. Sure you can do low level things with it, like inline asm, directly interfacing with hardware, coding for specific instruction sets like AVX etc, but that's not what a new user is going to go into. At worst the only extra things (relative to js) that a new programmer has to learn is memory management, pointers and compiling, which I would class as fundamental and put on a learners TODO list anyway.