We should be mad at Yahoo for having fucked up. If anything, they could have spun out the search part and be remembered for it,.
I honestly don't think it's possible to have a QA team large enough to handle the gajillions of websites that come up and disappear every day. They just have to come up with better and better metrics until they find one that approximates the human experience the best.
You don't have to cover the long tail... Maybe just top 10% of topics would be a big improvement.