To be fair, we don't know that any trailers have been cancelled. The info that was up on nba.com was supposedly sourced from someone not affiliated with EA or Live.
The main problem is that 2k has already released current gen and it is pretty good. A lot of the frustrating animation lock is gone. If the 2k next-gen trailer is representative of the final product on next-gen, then Live is really in trouble.
Live could have gotten out in front of this by being engaged with the fans and community. Show us some developer insights. Bouncetek is a neat idea, but it has to be seen in the context of the game to really understand how improved dribbling helps to get buckets.
So, either the witholding of info is calculated, waiting for 2k to show its hand first, or the game just isn't ready for the light of day. The first option is cynical and will backfire in reduced sales. The second option is par for the course.

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