NYC does a far better job at moving its citizens via transit than Seattle. As a result, NYC commuters are the least dependent on cars in the nation. For all of its inefficiencies, NYC is the gold standard of density here in the US.
During my trip to Seattle recently, I was really unimpressed with transit. It looked robust where I stayed in SLU, but it’s not really extensive. As far as anecdotes go, the one time I took the train, to get to SeaTac, some crazy guy tried to fight me.