1) 80% of subprime loans were made by lenders (such as Countrywide) which were essentially unregulated, inculding requirements to comply with minority lending targets.
2) Even in the case of the 20% of loans made by regulated lenders, it leaves out a whole bunch of other bad actors, for example the bond rating houses that should have informed investors of the actual risk, the people who misrepresented and sold the securitized results, and so on – and in the next few years we will be reading many, many account of such misbehavior as a result of both criminal prosecutions and civil suits.
Given the way the entire process was structured, and the enormous profits to be made short-term by participants, human nature pretty much guaranteed that in a poorly regulated envirmoment there would be abuse every step of the way. This was pretty much a classic case of market failure - and the banksters bought both the Democrat and Republican parties to make it happen
What would you think of the theory that rules the floodgates were opened for all kinds of funny-money tricks so as to make the CRA-induced funny money less visible. Something like the bank robber who throws open a suitcase or two full of cash so the mob that rushes in to grab the money will conceal him.