That's also how all patterns are constructed: present a plausible cover story (because it is true). Keep the underlings in the dark about the true reason for the system architecture (because the delta between the true reason and apparent reason is null). Don't write anything down (because there's nothing else to write down).

Suspicion of dark pattern is not proof of dark pattern.

(ETA: at Google in particular, the dark-pattern-conspiracy you're describing between two unrelated teams, in this case Drive and static storage, is hard to pull off because coordinating those teams requires documenting design, and it turns out a lot of folks working at Google are Hacker News-type personalities who will ask inconvenient questions if they come up. But what they have that we lack is observation of the larger security picture and the ways failure to, for example, 3PC-guard your static files can result in failure modes).