I do not totally blame the economist because of the bases and angles through which he formed his opinions or projections.
Firstly, he didn't expect that the government will suddenly make a U-turn to embrace bitcoin they once fought against. And this is logical but there is still a loophole for debate. This is because the government involvement didn't push BTC from below $100 to $100k

Secondly, he was looking at bitcoin from the currency aspect as was initially proposed by Satoshi and not as a store of value. Honestly, bitcoin isn't scalable to compete with Fiat.

So, his analysis then was limited by so many things and he was in a haste to judge a young technology.