The concepts of objects and ACLs are in the NT kernel itself. So things have worked like this on all windows versions built on the NT kernel: from WinNT 3.1, to Win2k, ... to this day. Windows TCPIP stack has improved since then, but I'd be _very_ surprised if ReadFile didn't work on sockets on XP (or anything NT-based, actually).
In any case, he's very rash to call out Windows when Linux has its share of special-purpose syscalls that do the "same" thing (e.g.: send, sendv, sendmsg, sendfile, sendmmsg, …) with myriads of options to alter their behavior.
