Since when does a handfull of close games equal a rivalry. Sure, whilst it's still going on you would like nothing more to beat the other, but in years to come, they it will most likely been seen for what it was. Two teams, both at their peak, giving their all.
Pies and lions fans have all (mostly) moved on. At the time, we would have killed to have got one up on the Lions, but we didn't, we move on, and now they're just another team. Hell, even the 'Dick Pratt Vs the ACCC' rivalry is bigger.
It was a rivalry at the time. It will probably fade, unless the Eagles and Sydney have some brilliant bottom of the ladder tussles in the years to come! Just because it isn't a longstanding rivalry based on tradition doesn't mean that AT THE TIME, it wasn't a fiercely contested and very valid rivalry. It was a rivalry built on close contests. As such, as soon as the close contests ended, the rivalry faded. Nobody is questioning that. After all, the past tense was used in the title. The rivlary WAS awesome at the time.