To me, mastering a language is knowing how to use it in a way to solve a problem in the fastest development time with minimal bugs and maintainable code which does not match up with code golf. C++ gives you lots of ways to introduce weird bugs which isn't something code golf demonstrates.
> So lemme ask you, can you name books (or courses) that teach C++, and devote a significant chunk (or any) of the material to cover such arcane syntax topics?
The C++ Programming Language book and Effective Modern C++ are good and they're full of "don't do this or something bad will happen!" parts. I'm not really concerned about a few arcane syntax problems but I am concerned that C++ has a lot of undefined behaviour that lets you shoot yourself in the foot in a way that other languages avoid.
> C++ is meant for low level system programming, when performance or size are constraints on the problem you're trying to solve. The problem domain itself entails a certain amount of care.
Agree with this but my view is you should avoid C++ at all costs if practical because of its productivity and bug risk impacts compared to other solutions. If low level is required though your options are limited.
> Also, JS and Ruby are indeed just as hard to master as C++.
We'll have to agree to disagree then because C++ is an order of magnitude more complex in my eyes. Code golf isn't a good metric to me as that's all about using obscure tricks to write as few characters as possible which isn't how you code normally. I would rather measure how easy it is to write code with minimal bugs and C++ gives you a million ways to shoot yourself in the foot.