Except that this guy doesn't know much about what's going on, apparently.
Fannie and Freddie were not authorized to back subprime mortgages. They were government-sponsored enterprises, and as a result, were regulated in many respects. This regulation precluded them buying subprime mortgages.
Where the problems with Fannie and Freddie came in was where there were no regulations and extraneous factors.
First, their balance sheets were not regulated. They could be highly leveraged, have an unsafe level of risk by having too high of a debt-to-equity ratio. Hence, even if they lost a little bit, they would be in serious danger of failing because they have no assets to back it up.
Second, rating industries such as the Standard and Poor and Moody's were corrupting the market, likely reacting to immense pressure from investors to get deeper into the housing market. They started rating a tremendous number of mortgage-backed securities as "Alt-A"--not quite subprime--even when they weren't.
Hence, many subprime mortgages were valued as "Alt-A," qualifying for Fannie and Freddie backing when they shouldn't have been. Since some started getting through into their highly leveraged systems, the defaults that they did end up seeing killed them.
Not to say that Fannie and Freddie weren't negligent in certain ways, but neither of them nor the CRA--which only government-sponsored enterprises were required to follow--had much of anything to do with creating this crisis. This crisis is a private sector problem the Fannie and Freddie happened to be involved in.