It's more a case of 9/11--To NYC'ers, it was their city being attacked, and was more an outpouring of local pride to come together in the face of a disaster. On the same scale as New Orleans folks coming together after the hurricane? Maybe, not quite as building-crumbling or rescue-team spectacular.
In LA, they're a little more sheltered from the world, and any disaster is seen as nightmarish if it might destroy their BMW, harm the resale value of their beachfront property and ruin their spa day. Post-9/11, we saw more disasters and more terrorist plots being treated as the End of the World, and what if it happened to YOU tomorrow??
If LA was hit with a real major earthquake (not like the one they wanted to handwringingly CGI-fantasize about in "San Andreas"), we'd see some people crumble and maybe the beginnings of some real city-community charity--But until it does, Hollywood still looks at 9/11, way over
there but they showed it on CNN, the way we did when prewar audiences let Europe worry about the war but then panicked when they heard Martians attack New Jersey: It's their problem, until all of a sudden it
isn't, and then you hide under your bed and want your teddy bear.
When we see a big terrorist attack destroy Big Ben and the Eiffel Tower in some summer blockbuster, it's sort of the same west coast mentality that gave us all those corny racism discussions in "Crash"--A wish to share in the outside world's problems by making it trendy, without having to experience them
personally, and then overreacting with gasps of horror if such things were to invade THEIR backyard.
Probably even more so for a German director, rather than an English director who actually had to live through the London terrorist attacks.
The first ID4 was riding on a new trend sparked by "Dante's Peak" to try and capture the 90's nostalgic wish for 70's disaster movies (and missing by a mile, because they were more in love with CGI spectacular than the Towering Inferno was)
But after the 00's, when Emmerich started typecasting himself with eco-disaster in Day After Tomorrow and 2012, soon every disaster and terrorist plot became Forever World-Changing, and it became a sort of Worry-Porn for the rich.
(And besides Spielberg was already doing Unhappy-Ending disasters first in "Peacemaker" and "Deep Impact", and that was even before 9/11, but that was
clearly more a case of CNN-Traumatized Rich West-Coast Guilt.)