As someone who knows C and not Zig, Zig is very interesting. It has incremental compilation, in-place binary patching, the ability to use code before declaration in a file, compile-time code execution, and extremely low compile times. Rust itself doesn't have most of those.
Also, as Python illustrated, a language doesn't have to be interesting to be popular.
As Python also illustrated, a language can be opinionated and popular. I'm growing more and more convinced that useful languages have to be opinionated - opinions have to be somewhere, and if they're not in the language (where the entire community is forced to use them), then they'll have to be in individual code-bases, where you'll get a bunch of fragmentation (which I think was one of the things that killed Lisp).
Now, Zig is very imperfect - no hidden control flow/operator overloading, no REPL, and a weak type system, most notably - but it's better than C in almost every way, easier to learn than Rust, and way more conceptually scalable than FORTH (which has a more "beautiful" design).