Steemit is mathematically designed to collapse in on itself (yes, I've read the whitepaper). The only question is when and if you can maximize your income before new users realize they can't make any money without significant luck or gamble on large power up investment.
The entire premise around upvoting good content is BS. Whales are incentivized to self-vote so they can make 50% per year. Medium sized SP accounts post crappy content all day long to self-vote and churn their followers who upvote in the false hope that this medium sized account will reciprocate some upvote love. There are literally posts like a picture of Hitler's head on a toilet (from our own profitgenerator here), or the dude that posts "random stuff from my bar" several times a day and makes $ because of self-voting.
Gone are the days of earning several hundred $ for a good post unless you are really lucky, or are a whale and voting your or your friends' posts. There are a few personalities that will break through (like Jerry Banfield who brought over his Youtube and Udemy following) and can churn out a living while the steem price holds. But as soon as user attraction ticks up, because people can't earn rewards anymore with so much competition and so little real upvoting, then the whales start powering down, and then the price will collapse.
TLDR: Steemit will collapse, but in the meantime, you can churn out some money from unsuspecting new users buying steem to power up their accounts.
Honestly, I've been on steemit since nearly the beginning. I have been around and seen how things have changed, how the new users come and go, and voting patterns.
I hate to say it... but I agree with most of what you have said...
I have called Steemit the free money fountain. The only way for it to survive is to either have an always constant user growth who buys steem (invests and highly unlikely) or by having someone keeping the price proped up (speculation).
The big issue is a cascading effect with payouts and Steem price. While steem goes up, so do payout valuations and people are more apt to buy or hold the payouts. But as it starts going down, so do payouts and people are more apt to sell.
As we saw last winter, payouts reach 0$ when steem price gets too far down, and literally this place was dying.
I'm honestly shocked steemit rebounded like it did. But when money is involved, people crawl out from the woodwork... so who really knows what will happen