The details: Maldonaldo was catching Hulkenburg's Force India. Maldonaldo made a pass attempt from wa-a-a-a-y back, and had to fight the car to control it on the exit. This required him to counter-steer to control some over-steer as he put the power down. Unfortunately for him, Hulkenberg was still hanging on around the outside, giving Maldonaldo lots of room. Not enough, as Maldonaldo's counter-steer thrust the Williams' front left tire into the Force India's side pod, and Hulkenburg was summarily punted off the race track.
Perhaps because it was Maldonaldo, who's shown no reluctance to bounce things off his car should it suit him, the stewards awarded him a drive-through penalty for "causing a collision".
Not "causing an avoidable collision".
I guess if you are the driver making the pass, the onus is on you to make it cleanly.
At least we have a data point to hang the stewards with in the future.