I think we have one of the best domestic T20 leagues almost by default mate - most of the others have been compromised by match-fixing or spot-fixing (Pakistan), the standard of cricket generally (West Indies), or by smaller grounds conducive to slog-a-thons.
At heart, we still see a "First Class" batsman when Australia bats in T20 cricket. Everything is based on technique, minimising risks early. Sixes are often a just a lofted extension of traditional cricket strokes - a lofted pull, a lofted cover drive, a lofted slog-sweep, a lofted straight drive. When was the last time you saw an Australian opener play a ramp or an upper cut in the first over of a T20I innings? Sri Lanka's openers in both matches have swung mightily from the off and the batsman that follow play without fear.
This is of course neither a good or bad thing. Australia's squad have mostly come from two rounds of Sheffield Shield cricket, whereas Sri Lanka have just finished a T20I and ODI series in South Africa, having been pummelled in the Tests. I still think that the international T20 game is viewed as a bit of "hit and giggle" by our fans. As a reference point, just remember the reaction after our Test defeat against South Africa in Hobart.