One option is to statically link against musl libc [1].
The kernel ABI is about the only stable thing you can rely on (which is something you _can't_ rely on for macOS or Windows).
In Windows's case, technically accurate but not really relevant, since the interface for working with the base DLLs like kernel32, user32, etc. hasn't changed.
https://stackoverflow.com/questions/3430400/linux-static-lin...
Can't imagine many Linux gamers are going to need NSS support in their game binaries. It's a bit of a stretch to say glibc doesn't support static linking, perhaps "officially" it doesn't, its just not all the extended features are going to work.
Static linking is generally going to be frowned upon these days however since you're effectively linking security issues into the binary forever.
glibc unicode tables are huge, musl are tiny.
glibc uses assembler optimizations for everything, whilst musl uses compiler auto-vectorization, which mostly beats handwritten assembly, esp. with constant arguments.