Its not that far fetched. 13's League, yes not a chance. But we are talking Brisbane hosting and commercial realities, league has political sway in NSW & QLD. So maybe 9's or Aus tag could potentially be promoted as an exibition sport.
Similar to 7,s a three day tournament during the Olympics could be a potential money spinner. That could go a long way to justifying its inclusion and it helps the QLD gov justifying the cost of the games, a feel good story for a strong local sport with International appeal.
In fact the more I think about it. Just imagine a 3 day sevens tournament followed by a 3 day 9's league tournament. You would pack out Suncorp for 6 days in a row, and just the local TV ratings would make it appealing.
The cost of hosting the Olympics have to be justified, so yes not so far fetched.