If you're not being facetious, then really, not much. You really can't go wrong with smart pointers unless you explicitly try to access the memory it handles rather than going through its normal interface (e.g., not using get()). Shared pointers are basically reference counted just like many other language handle memory management.
Of course. The point is that (IF there is enough interest in the idea) these rules are simple enough (in particular, they're inherently local, i.e. don't require analysis to go beyond one single function) to be enforced by a tool (say, built on top of Clang-tidy).
The author claims that the rules described, "extending" the standard C++, are enforcing memory corruption, and it is this author described subset that is still unsafe, not C++ in general. Think about english vs. americanized english, largely the same, but two distinct entities.
In C++, you are free to shoot yourself in the foot. In Rust, you have a Government inspector ensure that you always point the gun not just in a "safe" direction, but only toward a crosshair target at a designated gun range.
