One of my dad's friends growing up was a Chinook storyteller. Tribes on the Pacific coast have oral histories that reflect a long association with the sea.
Archeology confirms long occupation. Tools used to build plank houses were developed by coastal tribes using easily available local materials.
In much of the Pacific Northwest there is very little land to build on between the water and the mountains. And the most reliable food source was the ocean. Plank longhouses can weather typical Pacific storms. Other seafaring people used them (Viking settlements included similar structures). It kept people near their boats, which provided food, trade, and resources.
So please forgive me for accepting multiple strands of evidence that fucking boatload of tribes on the Pacific coast lived on the fucking Pacific coast including the oral histories of Pacific Coast peoples over your automatic authority over every topic on indigenous peoples.
eta: The largest settlements were in bays or sounds that offered protection from the worst storms but before we start splitting hairs, these protected harbors are part of the ocean.