Sounds like it is true. But I wonder if this is indeed the case, or it is only the case if you don't get through to Premium Desk?
Why I raise this question, a couple of weeks ago I was changing flight dates/times (not routing or carrier) on part of my DONE4 itinerary, the Qantas agent wouldn't do it without charging me a $125USD change fee, as I was "adding" a stopover ... so I went back and checked the fare rules rang back ... different agent and this time there wasn't even a suggestion of a change fee. Done with no fuss in a minute or two.
The first agent did not seem to be from Premium Desk, hard to tell, but just by the way he answered the call and responded to questions, seemed lacking the usual professionalism.
But of course it could well be the case that the fee is no longer waived.