You can't just magic more cargo shipping capacity out of thin air, the lead times from signing to paperwork to having a container ship sail out of the dock are

You can't just magic more cargo shipping capacity out of thin air, the lead times from signing to paperwork to having a container ship sail out of the dock are measured in years. It's also very much a boom and bust industry, and there has been a succession of past bubbles that has left shipping companies very wary of building extra capacity only for it to sit around unused.