[mnm2]

Any bank could "just" spend your money on your account

The central bank just prints money and​ thus steals 'value' from you (devaluation)

It's a matter of trust into an entity

[hashkb]

Ok, sure. Even if banks can be slimy, they can't be nearly as slimy as anonymous internet folk working in unprecedented/unregulated legal areas.

All trust is not equal.

[nv-vn]

He wasn't anonymous though...

[ubernostrum]

A bank is subject to laws, and generally believes that it is subject to laws.

Cryptocurrency people tend to believe that the stuff they're into makes laws and regulations obsolete, so who would bother writing up any of those?

[pythonaut_16]

Banks operate in a predictable, fairly transparent framework. Inflation devalues your money but the process of inflation is well understood and the occurrence/details are public knowledge.

Cryptocurrencies values can fluctuate rapidly and there's a strong precedent for your money disappearing in an exchange or otherwise.