A big chunk of the people working in the "office blocks" of "saving, lending, derivatives, FX and insurance companies" are there to deal with support and exceptions. This is a feature not a bug - if something goes wrong you want it to be fixed, especially when you are dealing with large sums of money. With smart contracts, if there's a bug it can't be fixed, if your money gets lost or stolen you can't get it back, if you lose your keys then tough, etc. This is considered a feature not a bug, e.g. to quote Satoshi "Lost coins only make everyone else's coins worth slightly more." However, in most people's view, this would be considered a backward step, and so not an example of a technology with a positive impact.