For a start, it doesn't have to be a dynasty - players can change clubs, you know?
The competition has been around for 120+ years, and could easily go for another 120. You think that in that time, there will never be another player to win seven premierships?
Really? It's not like he's some wild outlier - there are four players on six.
There's half a dozen current players who have played finals in ten years or more, and with player management and sports science getting better (not to mention the financial incentive) it's quite conceivable that 15 -...