He might be the better keeper in the long term, but he really hasn't proved it. In 2 big matches he's a bag of mess, probably our worst player on the pitch. He would have been a huge villain if the Alvarez shot bounced in.
I remember after 1 match people flocked here saying Ramsdale has never looked assured and give us confidence like him. Clearly not true. This guy is very shaky when pressed and kicks are all over the place.
But since Arteta wants to play in an extreme way, let's judge longer term before deciding.