Even bog standard C can be made safe, and include bounds checking if you create and consistently use an API that supports that mindset - see for e.g. Microsoft's string safe lib (not that I'm saying that is the epitome of such a thing).
However the will and the effort has to be there, C is an incredibly flexible and capable language and can be as safe as you want it to be.
The last Random ascii article I read, he found an easily exploitable buffer overflow in iOS simply by checking the code to see where it used memmove and worked out the exploit from there, guessing correctly that there was no bounds checking. So it seems that the usual culprits are fairly easy to spot, but somebody needs to replace the worst APIs with something safer (memmove, memcpy, memset, malloc, a = b).
Microsoft does it, because it comes along with SAL[0], which is kind of Microsoft's own Frama-C.
Also as long as WG14 doesn't care, everyone will keep passing char* around while hoping it is actually null terminated and points to the right place in memory.
Technically, ISO C could get safer types, or have something like SAL/FORTIFY, but as you say, without will it will never happen.
[0] - https://docs.microsoft.com/en-us/cpp/code-quality/using-sal-...
One is the naive one, someone that lacks the proper background and for whatever reasons thinks it is the only way, thus Rust.
Then we have those that are aware, but think all the other safety approaches are not valid for whatever reason, thus Rust.
Then we have those that kind of feel threatened by the security awareness that Rust brings into the picture, so whenever we talk about security, there is pavlovian reaction that it must be Rust when the subject is security.
Picking any language that embraces bounds checking enabled by default, and proper string/arrays, is already a major improvement.