The main attraction is Bitcoin and recently Dogecoin. BTC is slow and costly and mostly a speculative play. Dogecoin is a joke, but also worth billions.

Also these coins are speculatively often first, and useful second. Not all but many. Thus instead of being useful for exchange, they become methods of speculation.

It is also used for fraud a lot -- both various types of pump-and-dumb, Ponzi and money laundering.

And on top of all that it is usually inefficient.

So what we need are digital currencies that are fast, stable, and that can implement smart contracts (but these tend to be buggy as hell with no roll back.)

But that isn't what cryptocurrency is all about these days. It has been overtaken with speculation.

If we could get the benefits I outlined, that would be amazing, but it seems that very few are actually interested in that.