[Kansas Ref]

I have seen this play occur at times and have always seen it called a "tripping" foul on the defender despite the defender's being legally positioned ( as described in case play).
When that dribbler falls down while trying to force his/her ways thru traffic/split a trap., Refs always seem to mis-call it as a trip up and penalize the defender, but in this case doesn't the dribbler bear responsibility for the contact and their own resultant fall? Ergo, I wondered why this is so frequently mis- called, and I think its because of the appearance of a "body on the floor" must be a defensive foul instead of ( as Rule book says) a player control foul. I am vowing to be better with summoning up the temerity to call this situation correctly this season.