"Well, very simply, those with more stake are going to earn more in curation than those with less. To have a 50 cent vote requires 65,000 Steem at the current prices."

Exactly, which is why Steemit is nothing more than an illegal ponzi scheme. Newer members cannot possibly compete with long-time Steemit members who have high reputations and lots of Steem / Steem Power, and as a result get virtually nothing for their up-votes.

And that is why Steemit will eventually fail. No one is going to invest that much money in Steem in order to gain any kind of an advantage, and therefore they leave the Steemit platform just as fast as they came. Once long-time members cash out and leave, as they are doing in droves, there will be no one left to scam, and the platform has nothing else to offer. Thus Steemit will fold, just as it almost did last year when it was forced to layoff 70% of its staff.