how do you regulate something unknown, unless taking a hard regulatory line where nothing new is allowed (so stifle innovation)? what governement and others in power failed to do was ask why everything was peachy for so long, instead believed their own hype it was their policies.
they predicted a crash based on over-inflated housing, which any contrarian could have seen, and there was a degree of crying wolf. the scale of the crash wasnt just due to house prices fall (which recoverd remarkably quickly in US and UK - aren't we still in a bubble?), it was sudden...
its very different as they start with a depreciating asset and known risk, so priced accordingly. the issue with CDO and swaps was/is not knowing the true risk, or who actually had the risk exposure.
moral crusader might be strong but Carell character definatly portrayed as someone trying to teach banking a lesson. they (the real life people) were all in it for the riches.
yes, the accusation isnt they were responsible for the crash, but they had believed they were responsible for some economic alchemy, and they had budgeted years of spending increases on the back of this.