Steemit isn't a scam per se. It will be a scam if you decide to invest external currency into it. Barring that, it is a pump and dump, used exactly as that is defined.
By itself, Steem is a garbage cryptocurrency. But as a medium of exchange via blog posts, it has gained value (kind of like cacao beans thousands of years ago, or anything in demand but lacking intrinsic value). The sole reason it has value now is precisely so it can be pumped here and dumped for BTC on crypto exchanges.
Here's the rub. The major external cost is your time. When your payout doesn't adequately compensate you for your time, then it's either time to stop, or to stop expecting to profit.
I realized that I was never going to make what the whales are making. I have a job and a life outside of writing and posting content. So my frustration was reduced quite a bit once I stopped expecting to actually profit. I will still invest some time, but only on two conditions:
I must feel that what I am about to post is of substantial quality
I will only use time that isn't easily used on something more worthwhile