Meh. Like the word tanking, a lot of terms applicable to the NBA are being overused for shock value. CP3, Harden, Pierce etc ripping through the lane and flailing about with no contact is flopping (and sometimes they do it legitimately). Smart can be a flopper at times, but this is not an example of that. The NBA put together a series of flops and videos to show what a flop is and what isn't. Generally minor to no contact with over-embellishment is considered a flop. Taking contact and falling back when an offensive player rams their shoulder into you is not considered a flop even if there is some embellishment. It's accepted because it helps refs make offensive foul calls that they would otherwise miss. It's still a bit subjective, but this type of "flop" seems acceptable by the NBA guidelines they put out a few years back.