I know that proposing Rust in this case almost became a cliché but Rust's borrowing mechanism introduces such a semantic and ensures correctness in compile time. Moreover, with RAII it can also zero the memory after object is out of scope.
Ownership is for all structures on the stack. Box is little more than a rust-level wrapper around a raw pointer (well technically around a core::ptr::Unique which is the actual wrapper around a raw pointer)
Which part are you referring to with "only"? There's nothing particularly special about Box, at least, not in relation to the things the parent mentioned.
