Interesting problem but I think most situations are pretty simple.
I have received a bar of RAM in a box that could fit a small dog.
I applaude Amazon’s initiative to have manufacturers plan the shipping in the original packaging.
Maybe there are other factors, though? For example, I often get things from Amazon that are shipped in padded envelopes. The envelope then gets stuffed into my mailbox and bent. If it were a box, the mail carrier wouldn't try to put it in my mailbox because it wouldn't fit. So perhaps the packaging type selected statistically prevents broken RAM modules, even though it's too big if its purpose is to merely contain the RAM on a truck.
yeah I ordered a book that came with a cd from another market place, and the postman thought it fine to bend my envelope with my book a cd 90 degrees so it would fit in my mail box snapping my cd in the process.
You can easily brute force the problem for realistic orders from amazon.
What probably happened is the picker in the fulfillment center just had a larger box more readily available than a smaller box, so they took that one.
The person at the fulfillment center had to do 7 other orders that minute and gets fired if they fall behind.
Could it be the pickers are just not caring about the size of the boxes? They are supposed to be completing so many orders so little time that it's easier to just grab a big box they know is big enough while trying to get one more appropriately sized would take too much time.