Do you consider the GWS Giants a success?

I'd say that there are other reasons at play, some of which stem back quite a number of years. A lot of long-time fans of the game have become disillusioned with the code in recent times, largely due to the introduction of the NRL Bunker and a lack of engagement with the traditional working-class supporter base. The Super League war and the eventual formation of the NRL during the Late '90s has left the sport in a precarious state and one that rugby league in general has struggled to dig itself out of since then.

The executives at the NRL want to expand the game's footprint across the country and possibly into overseas markets, but it's doing so at the expense of it's traditional supporter base in NSW & QLD. The threat of relocation or mergers has hung over the heads of the clubs ever since the NRL was formed back in 1998. It's an ominous presence that just won't go away. Now there's talk that an existing Sydney team (which is tipped to be either the Manly Sea Eagles or the Cronulla Sharks) will be relocated to Brisbane once the current media deal expires in 2022. If either one of those teams is relocated, it would be the final death knell for many fans of the game. There is an underlying sense of frustration among the NRL's supporter base. 

Rugby league is definitely a spectator sport, very much so. It doesn't get the crowds that the AFL does (except for S.O.O and the Grand Finals), but the matches themselves have an electrifying atmosphere and really draw you in to what is going on (especially if it's a tight match). IMO, another main contributing factor to the differences in crowd characteristics between the two codes are the contrasting sporting cultures of Sydney and Melbourne. To me, the AFL is much more of a "tribal" sport and there seems to be more of an emphasis placed on barracking for your team at the grounds themselves. That's why Melbourne is often referred to as the "sporting capital of the world". It has a very strong sporting culture. 

I also feel as though the A-League has somewhat eaten away at the NRL's supporter base. Rugby league is undoubtedly still the dominant code here in NSW and receives the most media coverage, but the introduction of the Western Sydney Wanderers back in 2012 really lifted the profile of football in this state. It's not uncommon to see WSW jerseys/stickers or Sydney FC merchandise when you're out and about. Also, looking at that picture telemelbs shared, Sydney FC now has a higher average attendance than three of the Sydney NRL clubs.

Definitely agree. I personally do not know anyone who supports NRL nor have I had a discussion about it to someone before besides the grand final (and on here haha)