Still alive in the Sheffield Shield and in coloured uniforms in the one day cup. I think.
And it's Taz Tigers
You're right, the Bulls, Blues, Bushrangers, Redbacks, Warriors and Tigers still live on in the Sheffield Shield and the One Day Cup, though it is very easy to miss them.
On the BBL teams, CA wasn't sure how long T20 might remain popular for, so their strategy was pretty identical to what
@sempmrh outlined, minimal regional association and minimal brand depth.
It meant if it kept getting bigger they could just add more random colour teams, and if it suddenly shrunk, no one would be upset if some or all the teams disappeared.
Honestly it was not a bad strategy at the time, the old 'state' concept prevented CA from putting multiple teams in the same market and also it would have either limited player movement or added confusion (ie. Players plays for NSW Blues in Sheffield Sheffield and One Daters, but Qld Bulls in BBL).
Be interesting to see what the plan is for BBL teams domestically for the next decade or so. T20 isn't going anywhere anytime soon and the BBL, whilst it's metrics aren't heading in the right direction in the last few years, it's still the largest 'club' competition in Summer, cricket's biggest domestic product and a decent money spinner even if audiences halved.
As such, I wonder if they'll invest more into building the franchise identities, etc, or leaving it as is?