The major franchise tournaments like the IPL or BBL just get a bit boring after the first few games and no one really cares by the time the final arrives.
Certainly the case with the BBL this year. Attendance figures were pretty ordinary all year, but awful during finals.
08/02/20 BBL Final: Sydney Sixers d Melbourne Stars Sydney Cricket Ground 10,121
06/02/20 BBL PF: Melbourne Stars d Sydney Thunder Melbourne Cricket Ground 13,067
01/02/20 BBL KF: Sydney Thunder d Adelaide Strikers Adelaide Oval 15,995
31/01/20 BBL QF: Sydney Sixers d Melbourne Stars Melbourne Cricket Ground 13,275
Fair enough on the grand final because it was raining all day, but no weather excuses for the other three.
SCG holds 40,000, MCG 95,000 and Adelaide 55,000, so no surprises that there looked to be a lot of empty seats.
A couple of years ago the Adelaide minor round games were packed out.
It does seem that even the T20 format isn't enough to capture the short attention span of today's cricket 'fans', and the general public is voting with their feet.