Now that I think of it, the first game design 'textbook' I read had this philosophy where it discouraged details. Details were expensive... every little addition needed time and money and programmer/designers were expensive. Details were unbalancing, especially if mixed with the game mechanics.
Unless they could justify that those little details would noticeably improve the game or somehow add more income, the safe move was to not add them. Since an AAA's main priority is income/growth, why waste money on easter eggs that few will see?
Not surprising to hear, sadly. Art is about details. An artist would rather obsess over details than to drop them in the interest of profit. That might be the point at which one stops being an artist and is simply an entrepreneur.
Yeah, the business guys do have to keep the developers from exceeding budget. There's probably two profitable points - really early (the casual game approach) and with excessive details (the epic world approach, e.g. Blizzard, Bethesda, Final Fantasy).
Maybe a few spikes in the middle, but I think it's more that half-assed details don't add any value to games.
Agree with Graham though, that as time goes by, there's an 'inflation' of details. Back then, shooting a guy in the leg and having him tumble/fall on that leg was special. Headshots were a new thing. Having grass blow in the wind was special. These days, all that stuff is unnoticeable, and even leads up to higher expectations/disappointment.