Anything over 50k will be awesome. Wish we can get 50k plus attendances in Sydney. I know we can but people are either lazy or can't afford it. That's why Rugby League is the number one sport on TV, people prefer watching comfort from their homes!!!
I don't think it's that simple.
There are many valid reasons why Sydneysiders are more fickle than other cities when it comes to live sport:
1. Perception of travel to/from a stadium. It is not particularly convenient or quick to get from the Sydney city centre to Sydney Olympic Park for a major sporting event. Sure, there are direct trains from Central to Olympic Park for a blockbuster (e.g. SOO or Grand Final), but for regular H&A season, you have to change at Lidcombe. Compare that to the experience of walking to the MCG or Adelaide Oval from their respective city centres.
Access to SOP should improve in the late 2020s with a direct light rail service from Parramatta to SOP, but most significantly in 2030 when Sydney Metro West opens and provides direct access from Parramatta to SOP in just 5 minutes, and the Sydney city centre in just 15. That's quicker than from many parts of the Sydney city centre to Moore Park now.
2. Pre-game and post-game day experience. Is there anyone on this forum who actually enjoys the pre and post-game day experience at SOP? I don't. The place has literally nothing going for it on the micro scale - no density of good cafes, bars, pubs and restaurants, no density of pop-up food trucks, entertainment or activations - when compared with the likes of Caxton Street and Suncorp Stadium, or my 2 earlier examples.
3. The stadium itself. A key factor, and its limitations would have been debated broadly in various threads on this forum.
4. Cost of living. Live entertainment first to get the chop in a lot of households, and we all know Sydney is more expensive than other Australian cities.