[johnnydoebk]

>> write your own separate distributed cryptocurrency system

You don't need "cryptocurrency system" for most of the cases, do you? E.g. you don't need to solve double spending problem if all you want is a decentralized forum / messaging app / video chat. I'm not a decentralization expert but it seems to me, DHT has worked so far. And its advantage over Ethereum is that users don't have to buy some currency and pay for every message. They subscribe to the content they like and support it by hosting it. It's easy as that.

You need Ethereum if you want an easy ICO, but if it's a bad thing now, then I don't know why would anybody use it.