What kind of solution would you propose to folks like your boss?
One positive aspect I see about "rewrite it in Rust" is that you can to some degree expect a random Rust project to not leak and crash and expose vulnerabilities quite as much as a random C++ project. It's silly, but "written in Rust" acts somewhat as a badge of safety and performance, whereas "written in Java" and "written in C++" each only carry one of the two.
Of course, developer skill is also huge. You can write slow Rust code or fast Java code, yadda yadda.
One positive aspect I see about "rewrite it in Rust" is that you can to some degree expect a random Rust project to not leak and crash and expose vulnerabilities quite as much as a random C++ project. It's silly, but "written in Rust" acts somewhat as a badge of safety and performance, whereas "written in Java" and "written in C++" each only carry one of the two.
Of course, developer skill is also huge. You can write slow Rust code or fast Java code, yadda yadda.