Government programs do not explain why a bank would loan, say, $300,000 on an asset that was obviously going to be worth less than that in a few years' time. That happened with everyone's loans, not just government-promoted low income loans (which, btw, have a lower default rate than loans outside the auspices of the CRA).
There's no Government program that made it financially sensible to loan more money on an asset than the asset could possibly secure; the only possible explanation is either that the bankers were too dumb to realise it was a bubble, or they expected to be able to saddle someone else with the losses in the marketplace.
It's all well and good to say that the market corrects this, but when "correction" means ruining the entire financial system and impoverishing the country for the foreseeable future, it's time to reassess your chosen economic model. That is precisely what was going to happen were it not for government intervention into the mortgage/security scam, which, again, had nothing to do with government-sponsored loans.
You're not being in the USA and only getting some info via the MSM and a few web sites has skewed your understanding.
For instance, my house has appreciated since the housing slump. At roughly the same rate as before. The kicker is twofold: my house did not appreciate as much as the houses in the CA & FL & Vegas markets did before the bust and our neighborhood has very few home owning low-income minorities of the sort the CRA (& associated gov't programs) tried to "help."
The housing bust is mostly in CA, FL, Vegas and a few other markets. Not only that, foreclosures are concentrated in a a few zip codes in the effected states.
In my area, there are a few places where the housing values have slumped and it is predictable that they are in CRA-"helped" minority enclaves and McMansions at the edge of development, where one can drive 1/4 mile further and build new.
All causes lead back to gov't:
1. CRA & regulatory bullying
2. Capture/Corporatism with gov't (think Dodd & Bawney Fwank)
3. Fannie & Freddie
4. Risk evaluation of F&F bundled crap loans by entities pressured to rate them cheap
5. Land use regulation & construction regulation driving up cost to build locally
Accusing bankers & the market for this is like accusing Krupp & BMW for WWII. They had no power to make national policy and had no gov't goons to threaten violence if they did other than the gov't desired. They ended up instruments of gov't power & policy.