Yeah, I've lived and worked in/around Seattle since the 1980s - awful traffic is nothing new. Even back around 1990 it was ranked the 6th worst in the nation.
The people who think it's recently gotten much worse have likely moved here during the past five years or so. After the 2008 crash, traffic in Seattle improved a fair bit because a lot of people were out of work. It still wasn't great, but it was significantly better. Now that the economy is booming again, traffic sucks again.
I will say that, prior to the past year or so, northbound traffic jams heading out of downtown were a rarity... but nowadays they're pretty common. Thank heavens the U-Link light rail will be starting up soon.