I would guess that people leave because they realize that the amount of time and effort they have to put in is not worth it.
This has nothing to do with inequality, but a simple lack of equity. Do people quit their job in the real world because the CEO makes more money than them? No, this is the standard. People are very much used to that type of inequality.
If people could come to Hive and consistently make even $5 an hour they would stick around; especially people from developing nations where $5/h would actually be a pretty damn good wage.
On a real level Hive simply does not yet have the infrastructure to offer this kind of equity to the community. Blogging is a very niche activity. As more people try to earn from blogging massive diminishing returns kick in. At the end of the day we just need more jobs, and perhaps even training programs to seed them. 100% an infrastructure issue.
Is onboarding a pain in the ass? Sure? Is handling 4 keys a barrier to entry? Yes; many good points are made within your post, but none of them matter when people can actually come here and work for a fair wage. They can't so we're left wondering what the problem is and how we grease the wheels and fix it, but that is the core problem.
RE: The Impact of High Inequality on Hive