Re: Expecting perfection? You're going to be disappointed.
Were they 'destructive to society'? How easily you can forget the years of economic growth before the crash. Crashes are part of the economic cycle. They've always happened, and they always will. Anyone telling you otherwise is trying to sell you a book. Economics can reasonably be judged a success if the progress between crashes is greater than the crash - and that's been the case for a very long time.
But yes, I agree that our economic goals - or should I say our demands on economists - are both unattainable and mutually exclusive - which is exactly my point that choices have to be made, instead of naively believing that you can have everything.