What's amazing about Linux is that you don't have to use the system's libc, and you don't have to use dynamic linking.

That said, newer Androids use seccomp to restrict which syscalls you can use, basically to what bionic exposes anyway. This doesn't seem to affect Termux and friends, which can apparently run full X11 applications without root.

(edit) Notably, splice() is still callable, so maybe the POC needs to be tweaked...