It's just everything, even the micro details. He simply understands football at a level Antony does not. His movements and timings and his involvements and even the times he disengages to roam are literal leagues above Antony - like you can see the clear potential and growth path Amad had open to him with what he does.
Even if it doesn't work for him here, he's a top level talent in the making that we should always be aspiring to bring in, as opposed to Antony whose game unfortunately isn't even mid-table club standard.
You can envisage Amad having a solid working relationship with anyone who can play, and moreover, trying to understand how he can make himself useful to said player with his runs, passes and engagements. If you want to play some touch football, and have him at your disposal, how are you ignoring him for someone who cannot string 3 passes together?
Mind bogglingly bad management. Antony's not even better than him at defending and tracking back, which makes it even worse.