Totally agree with @igster and @charitybot. All valid points. For big names, Steemit is a good supplemental strategy to further cash in, but I believe it a difficult place to build a brand from ground zero.
For average folks, the long tail of prior work can be valuable. It gives a reason for grinding. One day, those posts on how to fix an Amazon Kindle will be found by the right people, who will be grateful and want to throw a little money your way. The more posts you have like that, the easier it is to have a sustainable income without trying to churn out "trending" posts.
Btw... I love Steemit and the community. I've been thinking about releasing a couple projects here, but this "7 days to $0" problem made me reconsider my entire approach. Instead of relying on Steemit, I'll simply cross post content here as a way to build a presence. For the passive revenue side, that will have to come from elsewhere.
The only form of passive income on Steemit I can think of is auto-upvoting, or creating your own bid bot... But those come with drawbacks if it looks like you're upvoting inappropriate content and your public-facing image matters. I'm fairly new, so I'm still trying to figure all this out. (Curating is not passive. And investing in Steem could be a passive income source if prices go up, but those funds may not be liquid enough in the short-term to cover costs.)