The reason is simple.
There is not much/if any reason to buy steemit to hoard. Because it serves only one purpose, in one location.
You cannot spend it anywhere else. And so it has no real world value.
Unlike bitcoin that can be used on over 300,000 merchant websites. Steemit is just a speculative exchange coin.
And so the price will at best ping-pong, or at worse drop when people sell.
There is no real world reason for people to DEMAND steemit to require buying it long term. But many reasons the SUPPLY grows and people will sell.
It essentially only has speculative value to day traders and no real value for long term hoarding or real world spending.
steemit has to either expand it. such as requiring a subscription to use steemit (to give reason to buy steemit for real use) or make content pay per view.
if steemit continues to hand out free coin just by someone liking a post. then its just a speculative inflationary coin that wont ever sky rocket.