Same could be said for C++, and yet while C++20 also doesn't have an official runtime on std (C++23 will fix that assuming executors land), the vocabulary types required for interoperability across runtimes are part of the co-routines design.
The std::future::Future from the rust standard library works with every runtime.
Not sure I understand, what kind of interoperability you are talking about. What kinds of code works in C++ across runtimes, for which the equivalent in Rust doesn't?
