The new virtual currency is not provided for anything, except by the demand of users. If interest falls, then the price for it, too, will go down with a stone. In other matters, the problem with security is inherent not only Bitcoins, all other crypto-currencies are also not provided with anything.
You're right and everything is true what you say but crypto has one big advantage over fiat and that's secrecy and decentralization. When perfected over time crypto will even exist without exchanges and fees.