Disagree but it's hard to tell how much of an effect AO has had as both AO and the reserves has come on at the same time.The recent drop off is due to Adelaide Oval.
An extra 15,000 at Crows games and 20,000 at Port game (lower base) is where the SANFL people are probably going...or dying off either way.
Direct evidence is that I haven't met one person say that they're not going to the SANFL because of AO. Yet I'd know 4-5 people that aren't going to the SANFL due to the reserves.
I'd think that most people going to AO that didn't go to the footy before wouldn't be going to the SANFL anyway and most people that aren't going to the SANFL now wouldn't go to AFL games either.
The drop off at SANFL level is largely due to the diehards being pissed off. Throw into the fact that Port reserves are going crap and you've got 1000-2000 per game not going due to that alone.