If <whatever language> makes certain assumptions and guarantees on behavior, then no, belief is not enough. It has to be plausible. GC alone really is a big issue and all the research (of which there is a lot) has not solved fundamental issues.
There are of course languages (like Rust) that have the fundamentals to match C/C++, but then it's still a matter of adoption. C++ also still develops.
There are of course languages (like Rust) that have the fundamentals to match C/C++, but then it's still a matter of adoption. C++ also still develops.