You are correct... steemit the way it is isn't worth investing time into, so creators mostly leave after a few weeks, I know a few others and I am a leisurely one myself.
There are newer networks where pundits haven't yet established themselves... a few creators stay here for whatever reason and people like haejin are successful because they sell content that others think they really need, or that will earn them money.
You know the principle "only sell to desperate customers" ?
So he has a great advantage there over others here because he's pretty prolific, obviously.
So haejin developed into the no1 goto address if you are looking for a positive market outlook, and that is what people always want...
As to the quality of his content, you can get the same or better on youtube, in any case you should be proficient at TA yourself after watching haejin AND others for a few months... but some will never be, and they need haejin, and haejin is obviously more successful on steemit than off steemit, so he will be a permanent phenomenon here.
In conclusion, steemit will either change for the better or stay the same, I see it as a tool to use - I tested it out and will create some content here, insofar as steemit is technically better at a few things than other networks, and worse at others, to share on those networks rather than here.
Sharing on steemit with neither desperate-customer content nor whale help seems to be a waste of time, and as a social network steemit is rather a ghost town anyway.