If that is true the rates for empty containers should increase making it worthwhile for ships to bring them back again?
This sort of implies that it’s incredibly cheap to make the container, and/or it’s expensive to add that weight to the ship, and/or our ports are incredibly slow at loading empty containers onto ships.
Edit: e.g. chop them, pack the result into containers, and ship it to Asia to use as raw materials for new containers.
The answer to China being better at 99% of manufacturing isn't subsidies, it's efficiencies.
There are so many insane distortions happening because of supply crunch that subsidies and trade nonsense are actually starting to become irrelevant. (though I really do hope USA sorts their shit out, their China policy is fucking up the world for zero reason).