The solution will eventually be similar to shipping containers. Every producer will have to use one of several hundreds (because of different sizes) standard ways to package something, if they want to sell with Amazon.
That's a possible solution but the fact it hasn't happened yet makes me wonder if there's a hard problem with even that.
IIRC the cost of processing in the 'fulfillment center' is way lower than the cost of delivering it to your door, so there is only so much benefit you can obtain by optimizing the warehouses.
Putting things into specific for Amazon containers for automation is going to be a cost to the manufacturers to modify their production lines to accommodate and may be more labor versus what they do today. Plus no matter what, it might be that Amazon has one package, Walmart wants a different one so you end up having a bunch of different packages that are all the same thing, which becomes harder to manage because you can't ship excess of the Amazon SKU to Walmart without repackaging.
I wondering if one country stepped in and called for standardized package (and fined those that didn't use it), would it be a tipping point?
How would a country (in the absence of egregious levels of regulatory capture) benefit from that? It would strike me as both ridiculous overreach, and something for which the only benefit would be some megacorp having the ability to cut jobs, while adding to waste (not all things need packaging!), reducing the capacity for manufacturers to innovate, market and reduce their own costs, and creating a system that would wind up rivaling the tariff code for complexity, all so that Amazon can sort and fill packages with fewer humans.