Yes; I would not be so adamant about supporting this idea if it weren't for my own personal experience.

I'm not sure if there are any serious proposals on the table on how they should be broken up; but I could imagine different companies that act as a gateway to selling on amazon. These companies would compete to offer the best experience to sellers. Someone more centralized higher up would regulate the companies that act as a gateway.

Amazon is so big that in my opinion it needs to have some incentivized structure that looks something like this. What they are doing right now is not fair and it is not working.