No one cares about the West Coast. There is a political cartoon that shows how outsiders see the U.S. New York is depicted as covering half the continent, with DC covering most of the rest. All you find on the West Coast is Hollywood and Disneyland. That is actually pretty accurate.
New York is where the NEWS exists. The three major broadcast networks, as well as Fox News are based there (CNN is in Atlanta, but how many people, even in the U.S. can find Atlanta on a map?), Wall Street is there, it has an outsized footprint globally. Hitting targets on the West Coast would have had no where near the instant international recognition that the Twin Towers did (the Hollywood sign, which what people would recognize, is on the side of a hill, all a plane hitting it would kill are some squirrels).
The whole idea of the attacks was two fold, media attention was secondary, the primary was to destroy the U.S. economy (Stupid? Yes, but there you have it). Nothing on the West Coast would have the desired effect, although it would have drawn the same level of U.S. response.
It has always struck me as a 2nd order Miracle that the attacks on the Towers didn't kill 40,000 people. What you always hear is how the engineers didn't account for the damage and that is why so many people died. Actually they did a magnificent, maybe even ASBish job. Those building had close to 150K workers and visitors in there when they were hit. Virtually the only people of that staggering number who died were trapped above the points of impact. Everyone else (~98.5%) got out (around 1 in 7 of the deaths were emergency responders)