Comment by nine_k

This assumes a perfect student who is not going to make any mistakes while writing their code, not even a typo. If an error is introduced, things become much harder on the C side. The compiler may miss it. It could manifest as a bug that only occurs in certain non-obvious circumstances, and manifests erratically (e.g. an out-of-bounds write clobbering data of a node next to it in the heap). Rust would most likely just not allow such a bug to be introduced.

In the same vein, driving on a modern busy road requires you to know about lanes, speed limits, various signs, traffic lights, rules of turning and merging, etc, etc. A road without all of that, where a steering wheel plus two pedals suffice, of course still allows you to drive, and drive fast, but it requires much more attention from a driver; many driver's mistakes are noticed later, and lead to more dangerous accidents.