If Lion’s Arch is destroyed, it creates a fixed point for characters to rally around, one that’s close enough to the present to be fresh in everyone’s minds for some time down the line. More importantly, it’s a shared experience for characters to bond over and discuss. Unless a character is an elite Pact operative, something like the fall of Zhaitan is not an experience that many residents of Tyria have had, and emotionally it’s not likely to be one that hits particularly close to home for the average citizen. Lion’s Arch, on the other hand, is important whether you’re Marshal Trahearne or some guy from Queensdale; even if a character doesn’t live or work or visit there, L.A. is part of Tyria’s cultural landscape, just as major metropolises are in real life. You can find this reflected in game: Very rarely do NPCs have dialogue about Zhaitan and the other Elder Dragons if they’re not actively involved in fighting them, and the plight of Nebo Terrace is only of vague interest even to humans in Kryta. Lion’s Arch is mentioned at least once in just about every zone in the game because it has immense cultural impact.
This means that if you’re just getting involved in GW2 roleplay, or even if you want to meet other characters and RP out in the open, you’ll have a ready-made topic of conversation. Almost everyone who belongs to one of the five playable races has a reason to care about Lion’s Arch being attacked and destroyed. Imagine if something suddenly obliterated a large part of San Francisco: Would anyone in the world be talking about much else for the next few months? Even if you’ve never found a hook for getting involved in long-running political intrigue plots or found an RP guild in which every necessary IC role hasn’t been filled, it doesn’t matter. Lion’s Arch is burning, and it will never be the same again. This is vastly traumatic, all normal social rules are suspended, and your character can definitely be forgiven for blurting out, “So how about L.A., huh?” to as many total strangers as they like, even if they have nothing else in common.
If ArenaNet continues with the living world story in this vein, we may have a game in which characters can always find current events to gossip or talk about outside of their own social sphere. The psychological impact this has on players can’t be overstated, either; part of the reason it’s not much fun to have yet another conversation about Nebo Terrace and its centaur problem is that there’s only so much going on there, and it may never change. In an area like Kessex Hills, though, the landscape really has changed dramatically. If ArenaNet can cover a zone with the wreckage of a giant tower and blow up the central hub of GW2, then maybe the rest of the world really is subject to upheaval at any time. That gives us reasons to care and to be invested in it beyond using it as a backdrop.
In addition, Bobby Stein has recently discussed plans to establish the living world story and personal story as canonically being a year apart, which is only going to make it easier for ArenaNet to portray Tyria as a world with a defined present tense. That huge rant I wrote about the cleansing of Orr some time ago may soon be outdated, and nothing could make me happier. I feel bad for Nebo Terrace and all, but making progress in Orr would be so cool.