Earlier quoted context omitted.
Isn't that the problem, though? Bitcoin was supposed to be a medium of exchange. Cash for the internet, in other words. Investing means that people really aren't going to be doing that, and it's just going to sit on a dusty flash drive on the shelf.
Not in the least. Bitcoin has many uses, and is a fundamentally new technology. Naturally it's going thru the technology adoption life cycle and every few months/years it catches up to the wider levels of adoption and more mature use cases. It will become a currency when most of it has been mined and it's in widespread use and there aren't billions of people who have never heard of it... the price will stabilize then…
I have literally only seen one use case where it makes more sense to use bitcoin than to use traditional currency exchanges and that is illegal markets.
The downsides (hard to use, one way transactions, high transfer costs due to low block size, super easy to get hacked and lose all your money...) all massively decrease it's value over traditional currencies. Illegal markets only put up with all of those downsides because companies/governments have specifically made it harder for illegal transactions to take place over traditional currencies.