At first glance, this observation might look correct on the surface but the real picture speaks of exactly the opposite. I came across an excellent post by @taskmaster4450 yesterday and I am going to use the date presented there to show that more steem is getting vested by minnows, dolphins and orcas. The 'middle class' SP group is growing in numbers!
The Steem whales are gradually losing their SP while Orcas are growing rapidly by accumulating more and more SP each day. Even Dolphins and Minnows are increasing their rate of growth. What is happening is that the wealth is becoming more evenly distributed. The best part is that red fishes and minnows are hungrier than ever and looking to gobble up more Steem by powering up.
As we can clearly see that although total vests of whales have gone down but Orcas are on the rise. From July to August even Minnows and Dolphins have shown an increase. I have condensed the data from its original format to a more easily readable one.
Over all we lost one whale but we also added ten more Orcas in this time period. We also added almost two hundred and fifty more minnows to the list. The number of minnow accounts have almost grown to eleven thousand.
Note: Following is the Steem user classification by levels
Whale: > 1 billion vests
Orca: between hundred million and 1 billion vests
Dolphin: between ten million and hundred million vests
Minnow: between one million and ten million vests
Red Fish: between 0 and one million vests