Supposed to be retired and past all this discussion. A few more points though.
ILA contracts have a number of accommodations for feeders barges and small vessels. I have always found ILA to be reasonable and focused on developing business not restricting new methods or ideas. Yes they earn a living wage with benefits, can’t compare US with 3rd world wages or conditions, in fact factor production US ports are not extremely expensive. If European ports are less expensive per move and some are it’s generally due to better terminal design and equipment not the labor force.
The small feeders pictured are comparable to short sea feeders US to Caribbean & Central America. If fact many vessels in these trades came from European feeder operations.
Self unloading chassis will never be seen in the US . Chassis weight would dramatically cut into cargo capacity. Almost all US distribution centers are level loading dock fitted. No need to drop containers on the ground.
Boats /3