(tl;dr the problem is people, not bitcoin.)

Any system of value will have people who exploit it or bend the rules, once that value becomes sufficient to be worth their while. This problem is due to human nature (at least some humans), and is independent of the type of value system.

So the question really is: is bitcoin less susceptible to fraud than fiat? The answer I think is yes, because of its decentralised nature. It does of course depend to an extent on your definition of fraud. If you think (as I do) that the 2008 financial crisis was caused by fraud and incompetence on the part of banks and governments, then bitcoin is less susceptible to that.