I can't help but think they're trying to fix something that isn't broken at all.

Adding new abstraction layers rarely helps when doing systems programming. You (as in "the developer") want to be as near to the machine as possible. C does this pretty well.

Perhaps I'm just getting old :-(

Then you are missing the whole point of Rust. The point of Rust IS to allow you to be close to the machine but while you maintain much higher level of safety. Rust is designed to do this with little overhead.

In this day and age with big software packages, security being an increased concern it really is high time programming languages do more to help us avoid bugs which expose us to hackers and crackers.

I do have an affinity for C, but as a Objective-C programmer currently coding in Swift, I am really seeing how many more bugs the compiler helps me uncover.

I think Rust is on the right track. It is a long overdue change to systems programming.

The proposition that Rust is offering is not new. In the 90s Modula-2 was touted as "a better, safer way" of doing system programming than C. It failed to get traction outside of education because it failed to offer a compelling reason for people to migrate. Those that do not study history are doomed to repeat its mistakes.

In the example given it's possible to write a similar library in C to protect against unwanted side effects or bad API design. I'm sure several have been written over the years.

Rust is a great language with lots of improvements over other system programming languages, but that is not going to be enough to get people to switch. You have to show that it's good enough to be worth throwing away 40 odd years of experience and well understood best practice. Something that is going to take a long time and big public projects to do. If just being better was good enough Plan 9 would have been a roaring success and Linux (if it happened) would probably be a footnote in history.

C and UNIX have survived as long as they have not because better alternatives haven't come along, but because the alternatives haven't offered a compelling reason to switch. Unfortunately at least now Rust is falling into the same category.

See also: Niccolo Machiavelli, The Prince