The zoning change is for TEU storage outside the port. The port itself was not subject to that rule.
The Port of Los Angeles is a landlord and is not directly involved in operations.
Private companies, such as APM, EverPort, and others, rent piers/berths and are responsible for the actual operations and logistics.
Some speculation: recently I’ve heard of some ships not even waiting to load empty TEU’s as they normally would and instead they are immediately leaving for China, literally empty. I suspect this behavior is what turned the congestion we had before into the quasi deadlock we have now.