They don't need to be as big as WWE. They do, however, have to turn things around. Their numbers are shrinking. Their live attendance has been going down tremendously outside of big events (like tonight), and their viewership has been slipping down significantly over the past year.
I don't think they will ever be as big as WWE. I want them to be a SOLID second place, though. Right now, professional wrestling in the United States is in a precarious position. No matter how good TKO is at letting WWE run things right now, they are still a corporation and can change their mind on a whim when it comes to decision making.
Wrestling needs a back up and an insurance policy, for lack of a better phrase, in which there is a national company not under corporate ownership that can keep the sport going should WWE end up in a bad situation in the future.
As such, AEW *REALLY* needs to grow its audience and get people interested again. They have lost their spark and they are in desperate need of freshening up. This is a chance for them to do so starting tonight, and they have got to take advantage of the position being offered to them instead of digging in their heels and swearing "everything is fine!"