It's kind of a joke. People getting rich off moving money around is kind of silly, and it would certainly be better if those jobs could be eliminated by machines.

Oh, don't worry. People will still get rich off of those transactions.

The vision of public blockchains (such as Ethereum) is to make the core of financial transactions automated and non-profit. While there may still be profit to be made on the margin (credit scores), the vision is that currency and equity trades will happen on decentralized markets that are automated and non-profit.

...Even if this vision occurs, it's not obvious how soon it would occur. For example, will we need stable-value cryptocurrencies before any of this can occur? Will anything significant occur in the next two years, or will it be five? OR more?