I really think this has to do with Bitcoin's price drop. If you notice the all-time high of STEEM was at BTC's all-time high. And in a way that makes sense. If Bitcoin is doing fine then everyone's perception may be that all other cryptos are going to be fine as well.
I just see these drops as a new opportunity to buy more Steem at a cheaper price.
Well, today there was a nice uptick. Probably because Bitcoin is having a nice temp upward boost.