Way out from left-field here, and multiply that by a loose jumble-of-thoughts..... so here's some conspiracy:
Shipping used to use primarily 'hemp' rope. "Manila Hemp" if I do recall. The fiber is strong and pliant. There used to be a LOT of hemp grown, for the rope business in both merchant and naval shipping. (fire in the rope-locker....)
The fiber from the plant is ALSO very good for other things such-as paper, cloth, (look at the prevalence of 'bamboo' in the past few decades) and such as well.
A 'softwood lumber' tree be-it Spruce/Pine/Fir takes ~70 years to grow to a reasonably produceable product. A square mile of said trees would need to stay dormant for 70 years, before harvesting again. Whereas hemp, in that same square-mile footprint, can be harvested to produce the same amount of fiber in a few years. (less than 10, and mostly less than 5)
Shipping and cartage mostly use Nylon lines, or some other polymer. Rigging is mostly done with wire-ropes now, with either chain or nylon slinging. But who do you think "behind the scenes" was behind the 'marijuana is bad' mantra, way-back-when?
If you think I'm completely nuts, and out-to-lunch, just do some of your own research of the "Softwood Lumber Agreement" and it's history. See the companies involved, the people behind the companies involved, the timelines, and the 'strength' they all still carry, today.
See where you're not looking, read what's not being written, and hear what's not being said.
OR, follow the 'news'.