I did a bit of digging. Total attendances are down every year (in football) since 2007 or so. There was a massive spike in 2001/2 after the qualifiers were introduced (as you'd expect).
Since the Leinster Championship has turned into a procession, the total numbers have slipped 28%.
Hurling is pretty steady, and of course this year, with the Super 8s and the Round Robin in munster, the GAA can point to the top level number and say 'See, people love the way we do stuff'.
The average attendances have largely been slumping since the qualifiers were brought in, which was one of my arguments against the qualifiers. The bank doesn't count averages though, it just wants to see the total revenue.
Even at that though, it's noticeable that the total figure has been declining steadily since about 2006, after the initial qualifier bounce, to the extent that the total figure in 2016 was 788,746, with 60 games, whereas in 2000, the final pre-qualifier year, the total was 686,553, with only 35 games.