I'm a bit kinder to the journos on this occasion. There does appear to have been some substantial, sudden downwards movement of the plane (to have pax "raised up" in their seats, etc). There were definitely some very scared passengers, and unless the quotes were made up, some "terrified" etc. pax. Frequent flyers forget that even today, there are novice flyers out there and any turbulence is disconcerting, let alone the sudden jolt (and a bit more) that evidently occurred here.
So, the journos, in the business of reporting this sort of thing, have reported it. No doubt spiced up and made to look more dramatic than it actually was, but can't blame them for quoting what pax told them.
The involvement of the QF Chief Pilot I thought interesting. He was essentially criticising the passengers for "not understanding". Sounded like a bit of over-compensation to me, deflecting the implied criticism of the QF crew for following too close to the aircraft in front. If this sort of thing happens regularly (and it appears it does), why get involved?