You might be able to (hypothetically) do it what might aptly be called Seattle's sister city, Vancouver, BC. You do still need to somewhat deliberately find a spot nearish the train, or a major bus route, or just bike, but it seems like it'd be more doable here. Haven't owned a car in years.

Last time I was down in Seattle though, I noticed they were building a massive elevated (40 mile?) train thing quite far north, which looks somewhat impressive if it wraps up in the near future.