Your argument is invalid.
Why? Because Sony Santa Monica is also "Sony's darling", and their recent GOW game did not gain as high critical acclaim as one would expect. Several critics lashed out at its level and combat design, and termed it as a game suffering from series fatigue.
Hype does not influence reviews. If it did, GOW: Ascension and Gears of War: Judgement would be 90+ games on Metacritic.
And the developers working at 4A Games are not new to the games industry. Last Light is their second title under the 4A Games name, but they've worked on Stalker in the past (a game which you PC gamers cherish more than anything lol).
So yeah, the challenge is completely fair.