Honestly, this sounds like a future headache that would otherwise go unnoticed unless the programmer is dealing with porting or binding over source code meant for older Windows systems to Zig (or supporting older systems in general). Eventually it might result in a bunch of people typing out blogposts venting their frustrations, and the creation of tutorials and shims for hooking to Win32 instead of the Zig standard library with varying results. Which is fine, I suppose. Legacy compiler targets are a thing.

This is already a problem with Linux binaries for systems that don't have a recent enough Glibc (unless the binaries themselves don't link to it and do syscalls directly).