This certainly had something to do with its popularity (The Phantom Menace was obviously responsible for a resurgence as well), but I was speaking in terms of longevity, & once JO & JA were released, JK was no longer the only game in town, & while there are various reasons that the community had mostly withered at that point, there were certainly games older than JK that still had respectable-sized communities with quality content still being created. I don't think that the netcode was the only thing that kept people around, but it certainly was an equalizer of sorts, & I think that it was a factor, though I have no evidence to offer other than a few HPB clan-mates that also played well past its prime. It certainly had something to do with why I played for so many years. I was actually turned onto Star Wars through JK--I thought it was nerd-stuff growing up & was under the illusion that I was too cool for that sort of thing.
This was both a blessing & a curse though, & I would argue that it was mostly the latter. JK was plagued by "hackers" ruining games & it ruined any hope of a competitive community--something that thrived in Q2. Yes, there are aim-bots & things like that in other games, but JK is on an entirely different level when it comes to hacks, & since LEC gave 0 ****s about the community, no reliable form of cheating protection was ever created. The few attempts made were easily bypassed.
Nearly all of MP was about prediction. You had to swing your lightsaber or shoot Force Destruction at where you thought your opponent would be. The whole grunt vs. screech phenomenon with lightsabers was one of the most painful but important lessons for newbies (a grunt didn't mean your opponent was hit--a screech did). It's incredible, when you think about it, how proficient people came at making these predictions at the highest levels. JK's netcode, despite its shortcomings, truly offered an interesting & unique MP experience. The best players became experts at pattern recognition, prediction, etc. The most significant side-effect of all of this was the resulting learning curve. Expert players could literally beat newbies in a uniquely embarrassing fashion--the guy who trained me in FF sabers beat me 75--75 the first time we played. I find this to be one of the most interesting things about JK & it's rarely ever discussed.