To add on another pitfall: iterator invalidation. In C++ you generally aren't allowed to modify a container while you're iterating through it, because it may re-allocate the memory and leave dangling pointers in the iterator, but the compiler doesn't check this. Rust's lifetime analysis closes this particular issue.

(Basically, the 'newer' C++ features do help a little with memory safety, but it's still fairly easy to trip up even if you restrict your own code from 'dangerous' operations. It's not at all obvious that a useful memory-safe subset of C++ exists. Even if you were to re-write the standard library to correct previous mistakes, it seems likely you would still need something like the borrow checker once you step beyond the surface level).