The problem is not the APIs, it's symbol versions. You will routinely get loader errors when running software compiled against a newer glibc than what a system provides, even if the caller does not use any "new" APIs.
glibc-based toolchains are ultimately missing a GLIBC_MIN_DEPLOYMENT_TARGET definition that gets passed to the linker so it knows which minimum version of glibc your software supports, similar to how Apple's toolchain lets you target older MacOS from a newer toolchain.
glibc-based toolchains are ultimately missing a GLIBC_MIN_DEPLOYMENT_TARGET definition that gets passed to the linker so it knows which minimum version of glibc your software supports, similar to how Apple's toolchain lets you target older MacOS from a newer toolchain.