References are not harder to use incorrectly. They are just as vulnerable to UAF.
Additionally, the security track records of large-scale apps written in modern C++ disagree with you. For proof, go to any browser bug tracker, or look at Pwn2Own.
You're really kind of changing the subject and trying to put words in my mouth here.
The reality is that apps in every language have security vulnerabilities and bugs, and different languages are more or less susceptible to different classes of bugs. Nobody is claiming C++ is perfect, and it's irrelevant to this conversation.
Getting back to my original point, even completely solving the memory safety issue, getting mainstream adoption for Rust will require competing with C++'s other advantages, like its huge ecosystem, and I think it's optimistic to think that will happen in just 3 years.
> The reality is that apps in every language have security vulnerabilities and bugs, and different languages are more or less susceptible to different classes of bugs.
Memory safety problems are on the whole much more problematic than the types of bugs that other languages admit, especially memory-safe statically typed ones like Rust. That's because they regularly result in remote code execution, which is among the most severe kinds of security issues. Nobody's claiming that Rust eliminates all security vulnerabilities: just a large number of the most severe ones.
> Getting back to my original point, even completely solving the memory safety issue, getting mainstream adoption for Rust will require competing with C++'s other advantages, like its huge ecosystem, and I think it's optimistic to think that will happen in just 3 years.
Sure, no argument there in terms of replacing C++. But I think that the idea that "C++ is too entrenched, other languages won't be able to compete" is very '90s thinking. Look at how dominant C++ was in the '90s compared to its status today. In the early-to-mid-'90s, you wouldn't think of building your company on anything but C++; nowadays, building your company on C++ (outside of a few niches like games or embedded software) is uncommon enough to warrant a blog post.
What I think is likely to happen, if Rust succeeds, is that it will continue the trend of chipping away at C++'s dominance in areas where Rust's advantages are strongest (safety, concurrency, friendliness to newcomers). It won't replace C++ wholesale, of course; C++ is immortal.
Additionally, the security track records of large-scale apps written in modern C++ disagree with you. For proof, go to any browser bug tracker, or look at Pwn2Own.