The problem is getting trucks to haul out of California, truck has to be ten years old or less, the driver vaccinated and willing to go to California. I don't know exactly how much that lowers the pool of available trucks.
I don't know the port capacity difference between California and the Washington/Oregon ports. But I can tell you that I am about 4 miles or so from a main east/west rail line. There is a pretty steady flow of trains with double stacked containers going past here. A train that is two miles long with double stacked containers. How many trucks would it take to haul all that? I see very few truck hauled containers on the freeway. I believe the truck hauled ones are just for local delivery. One day this last week I saw three trains go by in about 2 hours. All 3 headed west so I assume they were empty containers head back to China.