If people start to consider bound checking branches as overhead (which, in some extremely rare limited cases, they are in the right to do so), they should as well understand what happen with e.g. some largely used calling convention such as the one of Windows. Even in optimised builds, a unique_ptr for example can have an overhead compared to a raw pointer, IIRC because it forces going through the stack. If I remember my typical latencies correctly, for modern Intel CPU and probably a lot of high perf CPU, that can actually in some cases have a greater impact than an extra bound check...
So if you are in a so performance critical section that you start to care about the "zero overhead" kind of stuff and the cost of your (predicted) bound checks, you might be impacted by this non-zero overhead... (that is falsely widely believed to be zero!)
And don't get me started about debug builds with all mainstream compilers. The performance is then complete utter shit. This is made worse by the fact such an unsafe language needs debug builds more...
C++ was an interesting experiment in its domain, and has been and still is a success in some aspects, but honestly given core language modifications are needed to significantly extend the behaviour of core types (like vectors, unique_ptr, strings, etc. -- e.g. with the introduction of rvalue references and all the associated machinery and default constructors and so over), I'm starting to believe there are little advantages of this approach over integrating such fundamental types/concepts in the core language (I'm not advocating to do that for C++, I'm thinking about other/future languages). Then you can have more true "zero overhead" stuffs, whatever that means.