Another important factor, for me at least, to believe in steem's potential is the fact that "the rate that new tokens are generated was set at 9.5% per year starting in Dec 2016, and decreases at a rate of 0.01% every 250,000 blocks, or about 0.5% per year. The inflation will continue decreasing at this rate until it reaches 0.95%, after a period of approximayely 20.5 years." [1]
[1] Steem / Bluepaper
You bring up a valid point.
People on here look at this over 20 days yet the STEEM distribution is set over 20 years.
Anyone with SP is getting equal to the inflation rate simply by keeping their STEEM as SP.
So for the next few years, SP accounts will grow simply by 9%, 8.5%, and 8%...compounded.