I hear you and agree that disruptive tech can adopt users at an explosive rate. However I would argue that those had very easy-to-see utility for just about anyone at any age. You don't have to know anything to open a facebook acct - just sign up and start using.

On the other hand, Bitcoin still remains very misunderstood and you have to worry about private keys, wallets, cold storage, exchanges, masternodes, different exchange rates, etc. In other words, Its not that easy yet to get into.

In addition, the crypto market also doesn't have "a face" ...something that brings the market great news everyday. All the average joe sees is the wild bitcoin swings.

I'm a firm believer that blockchain will be a large part of the economy one day. 2017 was an amazing year for crypto. Its not hard to see the crypto market hit 1 Trillion within five years. 8T in eight years is possible but a lot has to go right for the average joe to believe in blockchain for that rate. I think 10-15 years we'll see the numbers you want.

Lastly don't forget that your numbers are for 16T (8 of which is bitcoin). That means 2B people total. In addition you are saying that bitcoin will hold the same amount of weight 50%. I can see bitcoin ruling for a while...i'm not so sure in the long-term.