I wouldn’t trust the Java app sandbox at all. They basically abandoned it.

The thing is the whole c program is unsafe. In rust individual parts are marked unsafe. This means auditing should be easier. Also being always on your toes isn’t really viable. Breaking down the program into safe vs unsafe is probably an improvment

In cases where bugs have been counted they tended to make up the majority of vulnerabilities. Chrome, Firefox, and Windows reported that around 70% of security vulnerabilites were memory corruption. Yes a subset, but the majority of the worst subset.