Go has GC, which has real costs always lied about because they are hard to tie to specific instruction sequences. So, Go will always be slower in certain key applications where latency matters, but in most other cases not so anybody notices.

Otherwise, there are too many differences in detail to generalize. Rust can take advantage of reduced aliasing that C++ can't, but the compiler doesn't because that code is still too buggy to turn on.

Last time I compared carefully, Rust and C++ built with Clang had identical performance, to well under 1%: much smaller than, e.g., the difference between Clang and Gcc.