[SrslyJosh]

A currency is only useful if you can actually buy things you need with it, and that means (among other things) you need its value to be relatively stable.

Everyone (or almost everyone) pushing cryptocurrency is, in one way or another, a speculator, so their incentives are not aligned at all with people who might actually want to use it as a currency.

[nicbou]

Even if you could do that, the barriers are insane compared to cash and cards.

Just the security practices required to avoid fraud are absurd, but since scammers can irreversibly empty your wallet, they're required. There's no credit card company to call, no fraud detection, no withdrawal limits, no way to lock your stolen card.

The same applies to personal information. Lose your key, lose your money. It requires the sort of data security and redundancy discipline that few people outside of tech are capable of.

[Tostino]

Few inside are capable of it for years on end without a mistake.