Crypto currencies have plenty of issues to overcome, but none are deal breakers and they can be accommodated as it continues to evolve. The current issue remains security of peripherals and the apparent gold rush among promoters, most of which cannot end well. Yet the pie is now expending through the steady advent of clones.
The current cap is running around 300 billion. Expanding by adding clones will allow the dollar total to continue increasing while prices actually drop. This will also allow many new entrants into mining operations as well.
What is rather clear is that this store of value is readily accessed by computer completely outside the banking universe and that banking security is provided by Blockchain. It is more convenient than banking for the right scale of transactions. It certainly will allow low fee international transactions and that alone is a huge market.
Gold has always been inconvenient. Fiat money has always been subject to government printing presses, and never more so that our era of quantitative easing. Now Bitcoin is convenient and now subject to taxation through inflation..