I think he’s talking about the underlying implementation of the CLR. From my understanding, he’s not talking about the interaction of the COM and .NET worlds. He’s merely telling us that they have used C++ and COM in the implementation of the runtime.
I was under the assumption it is perfectly possible to write .NET CLI compliant C++ assemblies that have absolutely nothing to do with COM / ATL / ActiveX?
Yes, you can use C++/CLI to create purely MSIL assemblies that have nothing to do with COM.