That 75 year-old man fell down on purpose. He looks to be pretty healthy and in shape. No way did he fall from such a slight nudge. Look at how he bends his one knee to cushion his “fall” and then immediately brings his feet together, crosses them after he “falls”. No flailing arms; nothing.
He was under no distress after he falls. Didn’t even try to hold his head after he “fell”.
He wasn’t injured other than he didn’t remember to tuck his head
That's my take as well...maybe he didn't intend to hit his head on the way down, but that was a NBA quality flop.