> What do you mean by 'people didn't want to live on the ocean'
I remember Arnold Schwarzenegger being confused why "nobody" wanted to live in Santa Monica or Venice Beach to a point that the government was subsidizing it to attract people.
For instance north of San Diego there are old apartment buildings on the water that have only window facing the ocean in their bathroom.
Historically ocean was considered as a hassle. You have to deal with the salty air that breaks down many material quite swiftly.
In Turkey, fathers would give the prime land to their sons (pastures) and the crap land to their daughters (ocean fronts). How the world changed.
> what do you mean by 'vast swaths of empty land in the PNW'
If you go anywhere outside of the majors settlements there are major swaths of empty land which is fairly cheap, but there is no infrastructure there and people don't want to be the city founders anymore.