Because it is already the best Batman game ever.
I had heard that Barbara Gordon as Oracle was in the game and that’s the first full on screen shot. Oracle has appeared off-screen in the first two games, this is the first time we’ve seen her onscreen as a character.
Actually it is interesting how Oracle continues to show up outside of the new 52 in DC Comics.
She just appeared in the Injustice Comic:
And of course we saw her in Li’l Gotham
Oracle was, of course, one of the most prominent PWD in DC Comics - tied to the Batverse, former JLA’r and the star of her own comic.
Currently in the New 52, with the cancellation of The Movement, there is no prominent PWD character
Of course, the bestselling comic in the new 52 will only be seen by 100K readers or so each month. Batman: Arkham Knight, if it follows the sales of its prior editions, will millions in its first week.