C programmers aren't complaining about the "magic" being tens of thousands of lines of code. They're complaining about the magic including bizarre side effects that brazenly violate the principle of least astonishment.

In C++, you can overload the comma operator to do shit. I've seen it done. There's no reason to do it, and no reasonable person would ever expect it in a code base they're unfamiliar with. To find bug in that ultimately roots back to that implementation, you have to go eliminate every other whack-job possibility before it even occurs to you that maybe the weirdo who wrote this code chose to overload the comma operator.

I'm not going to argue with anyone who wants to use C++ in their own projects, you do you. But let's be real about what C programmers are complaining about. It's not line count. It's syntactic obfuscation. I don't just level this criticism at C++ either. Basically every major new language has its own byzantine syntactic constructs to some degree.