Great post, Jeff.
There is one thing what I am very certain and confident :
Today even smartest brains are not in possession to dream and evaluated, into what all cryptos ( in general), and social minded STEEM (in particular) can/will evolve in 15-20 years.
Myself - I don't take a risk to forecast even 7-9 years ahead. And the time rolls fast. I still remember my very first mined BTC some ~5 years ago....