Interesting. One of Kurzweil's books was one of my most interesting reads when I was a teenie. Now I think he's wrong with his singularity theory. In his books from the 80s and 90s he has predicted much smarter tech for the 2010s than we really have ... (no, smartphones aren't really smart, they're just the Palm successor)
So his criticism to Bitcoin is that it is volatile. Well, here I agree somewhat with him. But I think that is not a problem without solution.
A decentralized "backing" mechanism could be one of the parts of the puzzle that leads to more stability.
There are some ways of finding intrinsic value in coins. I was quite interested by Byteball's idea of having 1 byte of data transferred on the DAG cost 1 byte in transaction fees. That means that the price of Byteball would theoretically stay the same as what people believe the utility of moving 1 byte of data is worth. Obviously in a speculative market this doesn't happen, but it's definitely an interesting example of an attempt to peg down cryptocurrency prices in a decentralised way.
What Yahoo's news site got wrong is making sure to talk about how Bitcoin's price has always gone up in the long term. This is somewhat true, but with all speculative assets and stocks there are bear markets. Bitcoin's last bear market was from the Mt. Gox crash to partway through 2015.
People only tolerate watching their money get worth less and less if it's gradually over a long time, like with (most) current fiat currencies. It's not so nice for them if they can't financially handle a drop of more than half over a certain period of time, which let's be honest is most people.
I think stability just comes from more support. Bitcoin volatility is a self-fulfilling prophecy for as long as people think the price could drop very low at any time. After a long time, the volatility will begin to fall if people have started feeling comfortable holding their money in it long-term.