Because you are. You likely wrote widly unsafe things which are perfectly legal in C++. Rust is really just enforcing RAII which C++14 already has, and you've likely avoided.
Of course, I'm aware that work on region systems dates back to the mid 90's, which is why I called Rust's borrow checker an “innovation” (the first time a product form factor or feature successfully makes it into a market) rather than an “invention” (coming up with a product concept that didn't exist before).
It's not just the safety features; it's the syntax, the build system, the numerous kinds of strings, the difficulty of finding up-to-date documentation, etc. Rust just has a steeper learning curve than many newer languages. This is not to say that the learning curve is unjustified; only that it exists and is significant.
Regarding safety, we don't even need to call into question my competence with writing safe code :) ; Rust's borrow checker currently precludes a swath of perfectly safe programs. This isn't a knock on Rust; it just means it's not yet intuitive.
Because you are. You likely wrote widly unsafe things which are perfectly legal in C++. Rust is really just enforcing RAII which C++14 already has, and you've likely avoided.