The only social media plattform I spent more time on so far is the Bitcointalk-Forum, but it was not about earning anything there.
I also want to point to the funny fact, that people automatically seem to assume I am just putting profane money in this project. No, it's actually much (unpaid) time AND money. So now what?
As to your investment, I see your point. But maybe look at it this way: I myself could sit back and just "Invest my time" (that's actually what is happening, because I'm tired of spending time AND money, if "time" is also a "valuable investment" here). Imagine everyone was doing this? Who's gonna pay for the value you perceive in the content? I get better content elsewhere for free, just because there are some ads on the site I don't really notice and never click on. I neither want to be mean, nor hate, nor spoil anyones party. I just try to be realistic. I already made the cardinal mistake of "falling in love with my investment", because I really like the Steemit and I want it to succeed. I just don't want that love to completely cloud my reasoning and I know what I am talking about, because it keeps happening again and again.