The Asian Cup and the World Cup are two completely different tournaments. Performing well at the Asian Cup is an important rehearsal for the World Cup. Ultimately, we can perform like we did this World Cup and play in the exact system with the same selections and probably make the Asian Cup semi-finals pretty easily but similarly we will fall apart next World Cup as well because it isn't the elevation we require with these players. The only argument to keep Popa is if he adapts his system to be more progressive in next 6 months and to be more forward thinking. If he can be less stubborn and defensive (literally and mentally), then it's an option for the sake of continuity but I, like others know that Popa doesn't retain that track record so why should I think he will adapt now?
You really get an extreme sense of how stubborn he is in press conferences, the insecurity through defensiveness. With quotes like "I don't regret decisions I make", complete old-school ways of thinking, complete bullshit and not helpful in anyway. He will die on the hill that we need to play the way he's use to. New Zealand, who have less talent than us, play more attractive attacking football than us. Even in four years when our players and team is projected to be a lot stronger, with the wrong system - we will still underperform.