Sure, both languages offer both generic comparison sorts†. But the defaults matter and as always in C++ the defaults are wrong, here it's reflected in naming.
That's not actionable information, except in the sense that the correct action is "don't use C++". Because sure, I know about sort stability, and I know about pointer provenance, and about memory ordering, but there might be any number of things I do not know and unfortunately in C++ "you should know and understand" absolutely everything at all times, which is not viable.
† The C++ standard library sorts are both much slower than in Rust, but hey, they're also both less safe so you're really getting the worst of both worlds
That's not actionable information, except in the sense that the correct action is "don't use C++". Because sure, I know about sort stability, and I know about pointer provenance, and about memory ordering, but there might be any number of things I do not know and unfortunately in C++ "you should know and understand" absolutely everything at all times, which is not viable.
† The C++ standard library sorts are both much slower than in Rust, but hey, they're also both less safe so you're really getting the worst of both worlds