Could someone who’s more knowledgeable about how Windows works than I am provide a semi-technical explanation of how this works?

There is a lockdown mode which restricted which COM objects could be instantiated from .net code to a short whitelist.

The whitelist is based on GUID. The lookup of GUID to actual binary is done through the registry.

COM hosting implementations should check that the object they got is the one they asked for. Net doesn't. So if you can write to the registry you can escape the sandbox.

Yeah. It's not as severe as the article makes it seem. It's just a bypass in a very insignificant component for which you need 2-3 other vulns to exploit.

I presume the editor just wanted to put an article out with Microsoft and Project Zero in the title, rather than analyze the actual flaw in the context of its severity.

The press had many problems, but this isn't close to a lie. Sensationalistic? Maybe. But to accuse the journalist of lying is claiming that the article is (1) false, and (2) that the journalist knows it's false. They're big claims, not to be made as throwaway snark. A functioning (and honest) press matters, and this does it and ourselves no benefit.