I've lived in Sydney for 10 years. AFL, whilst still well behinf league in popularity is becoming more accepted. A few points:
1. Some people sat Sydney is ready for another team in 15-20 years? It will be ready for one in 15-20 years if one is installed there now. I don't see a point in waiting and think the AFL should strike now when there is momentum and whilst they have cash to support a team.
2. I find it annoying in Sydney when I mention AFL and people look at you like you're a leper and say "huh? Why would you follow that?". And they're being serious. I don't excpect them to like the sport but I at least expect them to be educated enough to acknowledge it is the most popular code by a lengthy distance. It's like many of them think it's a crap sport that only people in Melbourne watch.
3. And the other thing is, people in Sydney aren't really into league. Some are, but most have a passing interest. They follow a team and hope they win, but never talk about it. People just don't talk about football/league up here. They're happy to bag GAYFL like it's a crap sport and think they're real League guys, but they're not really.
They just don't get it. They don't twig that they're not into footy like people in Melbourne, Perth, Adelaide, London, Manchester, Madrid, Rio etc. And it's because they have a second rate code. And they assume just because it's what they have grown up with and their favourite, that it must be a good game and the best game.