Earlier quoted context omitted.
Is NYTimes's use of Fastly also a cover-up?
Does NYTimes' use of Fastly subvert the meaning of the URL by literally covering it up in the address bar? Nope? Not the same thing, then. Personally I don't think there's anything wrong with the fundamental concept of signed exchanges. The only problem is that it's just that: a signed exchange of content, which should have nothing to do with the domain name authority in the URL. By all means, display "Content from:…
The issue is that the technical meaning of the URL is very far from what most user think of.
Is the URL an address for NYT's server? Not really because you are actually hitting Fastly's server. So when NYT sets up a magical DNS config, it suddenly is fine, but using crypto to sign the package and serve it on a CDN that way, then it's suddenly "subverting the meaning of the URL"?
We can have a real discussion of what the meaning of a URL is, but I think your interpretation is unfair. I think it's entirely fair to argue that it makes sense for URLs to be an address to a specific content.