Inflation is the catch 22 though. With a limited supply it seems like bitcoin may never successfully become a currency due to deflation, but at the same time without the carrot of massive gains you probably wouldn't have had any adoption at all. Most people owning bitcoin these days do it as a speculative investment, hoping that it'll be worth (a lot) more one day. It's not for nothing that the rallying cry of cryptocurrency zealots everywhere is "HOLD".

I think the root of the issue is that bitcoin was created in a vacuum. Some guy didn't start minting euro bills in his basement until France and Germany though "hey, we could use that". The financial systems already existed, and they created the currency to unify pre-existing European currencies.

Cryptocurrencies like Bitcoin don't have this institutional momentum so they need to reward its users to drive adoption, which is self-defeating in the long run because when I spend a 20 euro bill I don't think "uh, maybe I should just keep it for now, it'll be worth more tomorrow". Actually if anything I think the opposite due to inflation.