Railroad tracks run right to dockside in Los Angeles/Long Beach to the present day, a fact which makes fairytales about green truck mandates being responsible for the current goods bottleneck so recockulous as to cause open-mouthed gawping at the spectacle, and at the jackassery necessary to palm such a load of bullshit off as steak.
The fact that there are a finite number of berths, cranes, and longshoremen, with a commensurately predictable maximum number of containers that can be offloaded per hour, and thus a similarly predictable number of ships per day, expressable for one-, two-, and three-shift days, is rather tediously obvious to anyone who can do math with their shoes on.
You can't blame this on truckers or new truck regulations in CA
The RACONTEUR REPORT has this very solid analysis...