@cerulean Hard to say. In my opinion he was alluding to how classical chess is increasingly being dominated by openings. A small edge in the opening is enough to win in classical time control for players of this caliber. And similarly a drawish opening will end up a draw extremely frequently. So in some ways the world championship is becoming more about who did a better job of memorizing computer analysis than which player will be able to play better 'by hand'.
But in rapid, and especially blitz, this whole game changes since it's so much harder to avoid mistakes. So the opening plays a much smaller role, and the skill of the players plays a larger role. And I'd imagine it's certainly far easier to memorize reams of computer analysis than it is to stand toe-to-toe with Magnus in unfamiliar positions!