> BTC is failing as a currency because
    > it's in a speculating bubble

This feels pretty inevitable. There's no reliable tie to any economic activity, virtually no raw materials are priced in Bitcoin, and there's no central institution that can price stabilize, so pricing anything in Bitcoin (rather than: x USD/EUR/GBP/whatever as Bitcoin) seems a long way off.

It's also -- comparative to fiat or commodities -- massively untested, so price shocks seem inevitable. Regulatory or technical risks that could reduce (or massively inflate) the value seem almost certain.