Libc isn't just an ABI, it's a library - one that relies on an opinionated runtime. That's the demon, it's incidental complexity that has been ossified by past

Libc isn't just an ABI, it's a library - one that relies on an opinionated runtime. That's the demon, it's incidental complexity that has been ossified by past design decisions. There is no fundamental reason that interacting with an OS has to require anything more than the minimum necessary to transfer data to/from the kernel (e.g. supervisor trap instruction).