The finale must have seemed like absolute horseshit to the Jinxers. They spent what seemed like several months resisting Piltover's violent occupation of Zaun where they are regularly harassed,
shot at, and plainly intimidated in their own homes.
All for it to mean nothing, because everything they did had no bearing on Piltover's decision to pull back the occupation. And after what seemed like months of being terrorized they're asked to join a fight of which it's catalyst and driving force is hextech and it's creators. A technology and group of people that have never directly or indirectly benefitted them in any tangible way, and didn't one of those guys kill a kid in Zaun a couple months back!?!?!???
But it's the end of the world so of course they're going to fight, and of course many of them died. Some worse than others, in the uniforms of the forces that beat and imprisoned them.
On the battlefield all the double standards are laid bare for them to see because Piltover has fully weaponized hextech to defend themselves from an aggressor. Meanwhile one of the core reasons their home was gassed and occupied was to rid the place of shimmer. Without it Zaun was easily occupied by Piltover and they died in droves on the battlefield from wounds that it would have easily healed by it.
And after everything that's happened, from the invasion of their home, the violent repression, the deaths of their leaders and their symbol, they gained practically nothing in return. Even the power Sevika gained as a councilmember is completely dependent on when a Piltovan deigns to side with her. What's worse, there's literally nothing stopping from Piltover from doing it all over again. Piltover didn't need hextech to occupy Zaun, without shimmer, all they needed was their guns.
Obviously, this isn't over. None of what's happened will be forgotten, especially by the faction that appeared to spend the most time fighting the occupation. Even though they've gained nothing of material value from Piltover, the connections and skills they've forged in the conflict are decent substitutes.
Some of these new skills include gunsmithing! An incredible development in Zaun as only Jinx and Piltover had a monopoly on the technology. Add to that the fact that the Jinxers don't just admire Jinx, but likely Silco as well and are even depicted fighting the enforcers alongside Silco's former underlings, there's clearly a new wave of militancy brewing.
This leads me to wonder if over time the Jinxers would morph into something like the Inx. The Inx are of course a noncanon Jinx-aligned faction, but their creation was heavily inspired by Arcane and even included Silco's iconography in their aesthetic.
Now first off, the Inx are dangerous. They're violent, obnoxious in a hooligan kind of way, and they operate kind of like a cult (real estate fraud and all), but they're also the kind of dangerous Silco enabled in Jinx. Leading members like Chadd above are artistically creative, inventive, charismatic, and genuinely well-organized.
The Inx are incredibly capable of amazing feats (and great music), they're just sort of directionless, and the Jinxers have an ideology that's likely to only get more extreme and a real enemy, but little in terms of power. With a foundation like the Jinxers, something like the Inx could form in Zaun, but far more dangerous. Post-finale the Jinxers will likely be the ones to invest their time in making Zaun's next generation both as innovative and dangerous as possible to make Zaun's streets as uncontrollable and terrifying for enforcers as when shimmer was around.