What problem does zig solve?

Hi, I used zig for advent of code and really enjoy it. The code is simple, elegant and has no background magic (although spending more time fiighting the compiler than writing code is a little frustrating)

I heard that the idea for zig is not to replace C completely but to write new programs in this modern language and plug it with C codebases.

What is the purpose? From an economic pov I don't think companies will switch to new stuff. it's not convenient unless the tech is groundbreaking. But what is the groundbreaking thing about zig? Fast compile times? Fast code? Safer language (from undefined behavior)? A modern and more consistent solution for the low level world?

Is there like an idea of the path to transform it into a madure language?