This is perhaps the main point of this article. They needed `unsafe` to implement a safe way of concurrently modifying a single contiguous buffer, which is not allowed in safe Rust.
Could such a workaround come to the Rust language in the future. Maybe other programs will need a "safe" way to implement something similar that is currently impossible with the safe methods offered by Rust.
But why? That’s is exactly the reason why unsafe exists: to open an escape hatch to do something that is impossible to do in safe Rust (and then wrap that under a safe interface). Your safe Rust, standard library, is constructed exactly the same way: based on unsafe.
Unsafe doesn’t magically make your code unsafe, it’s just that you tell the compiler to trust you to handle the problem correctly (usually by meddling directly with pointers).
What would most likely here would be abstracting this problem into a library that could isolate "unsafe" in a place where it could be specified, tested and examined in isolation.
You could add this to the standard library in the future. There is already the 1d version of this (slices). But you don't need to - it would be perfectly fine to live on its own.