That might be part of it too. I worked from home. I lived in Capitol Hill, parked my car in the garage, and I think I drove it maybe once the entire year I lived there. I walked everywhere. Folks were pretty friendly.
After fifteen years of living here, I've concluded that a large part of the traffic woes are brought on by the general driving habits of the residents themselves. Can't properly merge (speed up to the flow of traffic, please), can't stay out of the left lane, and huge gaps are often left because a driver can't be bothered to push the accelerator (exacerbating the jerky stop-and-go). Seattle doesn't need more roads, Seattle needs to learn to operate their vehicles (though Seattlites will tell you it's the immigrant Californians; talk about denial). Contrast to, say, NYC where it appears to me that everybody just wants it to work and if you're screwing it up for everyone else you get a horn and a finger. Which, despite stereotypes, doesn't seem to happen all that often (disclaimer: never lived there, visited lots) because everyone else wants it to work, too.
That, and they should have said "yes" to federal light rail dollars forty years ago. Now we're stuck with a tunnel that I'm becoming increasing convinced is never going to get finished.