Ah, but then you have potential interop and portability issues. C11 isn't yet universally adopted, and there are some dark corners out there where even ANSI (C89/C90) is not quite embraced and original K&R is holding out.
I think the jury is out on Zig and Odin (but I like Zig a lot, in particular), but I feel Rust has hit a tipping point - like Go, Python and Java - where there's too much production code out there for it to disappear in the next ten years.
If you were to ask me about languages where that might not be the case in ten years, I'd point to where usage is not very production oriented (R, Julia), or where people have had a good try and decided they want to pull back investment (anecdotally, Ruby and Scala seem to be on that curve right now).
Nothing really disappears, the question is how strong the ecosystem is in ten years and how good the support for the code you write today. Rust will not go away but I doubt that the code written today still works without hassle or that all the 1000 crates it depends on still exist. That there are dark corners using C89 or K&R is not a weakness, it demonstrates how strong the C ecosystem is. If you write something in Zig or Rust now, you need to realize that in 10 years it might also be considered ugly legacy code, even if you think it is shiny modern code today. The question is then if it is as easy as using "gcc -std=c89" to work with it.
I think the jury is out on Zig and Odin (but I like Zig a lot, in particular), but I feel Rust has hit a tipping point - like Go, Python and Java - where there's too much production code out there for it to disappear in the next ten years.
If you were to ask me about languages where that might not be the case in ten years, I'd point to where usage is not very production oriented (R, Julia), or where people have had a good try and decided they want to pull back investment (anecdotally, Ruby and Scala seem to be on that curve right now).