> "high level assembly"

That's already a fundamentally wrong assumption :) With today's compilers, C is a high level language like all the others. The optimizations happening to C code are not fundamentally different than for any other compiled high level language.

> We should discourage the usage of C in application programming and prod application developers towards memory safe languages like Rust or Go.

No that's rubbish, just as it would be rubbish trying to 'discourage' people from writing programs in assembly code or any other programming language.

Ultimately, guaranteeing "safety" is the job of the sandbox your untrusted code is running in (e.g. the browser, operating system or VM).

The only difference between Rust and any "unsafe" language should be that one fails already at compilation time and the other at runtime (because the sandbox killed your rogue process).

E.g. if an operating system is exploitable because it allows untrusted programs to leak out of the sandbox, then that problem must be fixed in the operating system.