Tour elementary schools across the nation, and you'll encounter lines of cars waiting to pickup/dropoff children. This is emblematic of the shift that has occurred in pockets of American society--the needs of the individual over the good of society.
Seattle just has unique geographical constraints that exacerbate the issue of individualistic thinking.
Actually they are. Humans are notoriously bad for understanding risk.
The rise in helicopter parenting DESPITE the fact that in no time in American history have children been more safe [1] is due to the fact that we (parents) have access to more information and news, and stories of children being harmed are sensational.
Our children would be fine riding the bus and waiting for the bus stop like we did as kids, but the fact that it's MY child means that I must do everything I can to protect them, regardless of the rationality of it. It is very much about individualistic thinking.
1: https://www.childtrends.org/indicators/infant-child-and-teen...
And then they have kids so everything turns into "that will severely impact my family and my children" so the rest of us are monsters for proposing such a thing.
Sorry for being hyperbolic; this raises my hackles a bit.