I actually recommend reading some of Nouriel's thoughts on the matter. I don't recommend taking investment advice from him, or anyone else for that matter. Do your own research and your own critical thinking.
I believe there is immense value in a global currency that doesn't have uninvited middlemen. I also think the immense volatility will slow as people come to understand what cryptocurrencies can represent and better solutions arise.
I've basically been out since then, but might be jumping back in to running a multi currency mine if the stars align right. Again, I don't really care about it as an investment vehicle, I think the technology is interesting and I'm good at the ops around it.
No one really knows what the whole thing is going to be, I think bitcoin, with all it's flaws is here to stay but I think persistent information and decentralized network address resolution is WAY more interesting than money laundering, day trading, buying pizza, futures, ICOs, or buying drugs.
The day I turn on TV news to tell me about my budding technologies is the day you can just dump me in the river. Seriously though that guys yowling doom and gloom is either just ignorance or he's got a bridge to sell. I don't need to google him to find out which.
Was that sarcasm? Because if not, you're completely divorced from reality.