I don't get the Arab hate either. I've been around them my whole life, and out of those I've owned two that I wouldn't trust with kids. Both of them were mistreated before I got them. The rest have all been extremely trustworthy, especially with kids. I think people just see Arabians in their "show off" mode and think that they're like that all the time.
On the other hand, every Quarter Horse I've ever ridden was a total nut-job. But I don't make generalizations and say that all Quarters are like that, I was just unlucky enough to find a bunch that were.