The thing about these newer C alternatives, is that they have to provide compelling reasons for people to want to use it. Not just be a little more modern than C, but features that put it over their competitors.
In the case of Rust, at least they made safety a thing to hang their hat on. As an competitor, how do you "out safety" Rust?
Golang carved out a nice niche for itself, and the involvement of one of C's original creators and Google backing it up sure did help out. And Golang has ignited a group of its own alternatives like Odin and Vlang.
Not sure where Hare can find a niche that isn't already occupied or how it's going to make people want to jump ship to them.
Rust is still not totally safe. There's quite bit of code out there that needs to be panic safe, run within a statically-sized arena, be guaranteed to always terminate/progress and so on and so forth. None of these things are ensured by Rust at present (and common language features like arbitrary function calls get in the way of them), while Ada/SPARK and the like at least make some effort to guarantee those.
It's not that hard to out-safety Rust, with its unsafe operations and FFI. The Actix fiasco a while ago was a good example of this. Javascript is the gold-standard here IMO. I can also imagine a systems language that is much safer than Rust, it's not hard if you're familiar with recent developments in the PL realm.
In the case of Rust, at least they made safety a thing to hang their hat on. As an competitor, how do you "out safety" Rust?
Golang carved out a nice niche for itself, and the involvement of one of C's original creators and Google backing it up sure did help out. And Golang has ignited a group of its own alternatives like Odin and Vlang.
Not sure where Hare can find a niche that isn't already occupied or how it's going to make people want to jump ship to them.