As much as we can highlight past mistakes, it matters little at the 2020 selection table.
White's 2019 form was outstanding, especially given Cheika's constant switching in both the 9 and 10 position. If he can produce that form then he's in the 23.
As much as I like Powell, I'm just not sure he has that class edge to take his game to the next level. Good super player, can do a job at Test level if we have a few injuries, sure. The Hanigan comparison is pretty valid IMO, or maybe a guy like Bryce Hegarty. Not much wrong with his game, just maybe lacking that last 10%.