They've been using safe languages like Ada and SPARK2014 for decades, and those are hardly unsafe. In fact they are safer and more mature than Rust and easier to learn IMHO.
Well, COBOL just got ISO COBOL 2023 out of the door, and both Visual COBOL and NetCOBOL, still offer a much better development experience than many FOSS toolchains.
Controlled Types and SPARK provide the mechanisms to deallocate only when it is actually safe to do so.
Additionally unbounded collections, are just like graphs in Rust, they provide safe ways to managed dynamically sized collections, while hiding the unsafe code in implementation.