because you have to interact directly with hardware at a low level at some point (poking registers, implementing syscalls, implementing process and memory addre

because you have to interact directly with hardware at a low level at some point (poking registers, implementing syscalls, implementing process and memory address space isolation, context switching between rings, etc), that will always be inherently unsafe. Userland Rust depends on these guarantees to provide safe code, something has to implement them.