Another option is C#, it keeps getting active development, is the closest[0] in performance to pure unmanaged tier of languages and has tooling similar to Rust's cargo, isn't being abandoned any time soon (it's a core dependency of msft and seems to be increasing in amounts of promotion (finally!)), and has other industry players also working on it (like Unity).
Golang is popular enough that development would continue even without Google. Could be a fork with a different name if needed, but it's not going anywhere.
