You have just let a lot of people let off steam, and I will be one of them.
Most people genuinely want to help. At least I do. However, the structure of Yahoo Answers is such that any response is capable of earning points. What the points are ultimately used for is a topic for another time.
So, people who want to get points any way the can, even if they have nothing to contribute, answer with anything that comes to mind. The people who are abusive, are just trying to show that they ar e better than...and in control. Putting someone else down is just a mechanism for trying to raise yourself up.
Yes, it would be good if Yahoo Answers had better filtering, but realistically, human nature would find a way around any barricades.
If you look back at the past, the same thing happened with CB radios. There was a code of conduct, and it was enforced by the users. Then bad language and other vioations crept in. Sooner or later, the users got used to it, and did not report violators. If you want to keep this forum clean, do your duty, whatever you decide it is.