Microsoft Newspeak.
The Service Interface of WCF is an implementation of RPC.
Quack, Waddle, Duck.
WS-MAN (WinRM) is emphatically not RPC (DCE) based. It is SOAP based. There is no IDL, no huge range of TCP ports to firewall, no 32-bit/64-bit argument translation, just XML. There is no ‘remote procedure call’ per se, but rather alerts (like SNMP traps) and info requests (like SNMP queries). WinRM is based on WMI, which is more closely related to SNMP (with its MIBs) than any RPC implementation like OSF DCE or Sun XDR/RPC.
WCF is just a .NET API for communication. It is orthognal to RPC and WS-MAN (it can access both).