You care because you need to have a c compiler installed, as well as the libc stuff… It is a giant pain to do so in some circumstances. One less dependency is a good thing.
100% of platforms that Zig & Rust run on already have a C compiler installed, though. A c compiler being present is the baseline assumption. If Zig existed in places C doesn't and I wanted to write C for that platform then having Zig CC would be an advantage. But such a situation doesn't currently exist and seems unlikely to ever exist? Especially in the context of a library/module porting to Zig or Rust piecemeal, though, then I already obviously have a working C compiler & build toolchain in place since that's my start point.
You might not be aware that Zig runs perfectly fine on Microsoft Windows, without MSVC installed. Consider also that installing Zig on Windows is a matter of unpacking a 40 MiB .zip file, whereas installing MSVC on Windows requires downloading something like 8 GiB, being an administrator (!!), and restarting the computer twice.
you may have one. Not everyone does, or should. It is a massive pain. See how many folks complain about various native wrapper packages in Python and Ruby for example. Someone even made a Python wheel wrapper for zig to make it easier to compile C extensions.
Yes, most of my systems have "zig cc" as a C compiler installed nowadays. Why? It's so much easier to install. Especially on systems like windows, and i get other benefits. One example: "I can send you a project, and you can just compile it." Dependencies? "Zig toolchain, any OS"
I haven't had this experience with any other language. When a package manager lands, you won't even have to install any SDKs by hand anymore.
I quoted from cc’s readme above.