There's quite a bit of misunderstanding in that post, especially with respect to systemic weaknesses. And a lot of unsubstantiated claims and terrifying graphs (like that tweet graph as something desirable for currency inflation - what it also implies is your savings going up in smoke).
I'd love to find an in-depth debate on Bitcoin from an economic standpoint, but this is not it. It's just more of the same half-understood FUD. And it is a horrible idea when half-understood - IMO, it remains to be seen if it's a horrible idea when fully-understood.