Yeah sure they do more things than only doing the syscall, that's the point of an abstraction. But they still provide the functionality of the syscalls, just in the abstraction that you want it to be exposed as in the programming language. That's what I would consider a wrapper.
> C is used a lot in embedded projects.
Sure that's a freestanding implementation, which primary distinction is that it doesn't rely on the libc. The notion of the libc being part of the OS in the wider sense, still holds water here, since here no OS corresponds to no libc.