You'd think so,but education and experience doesn't really get rid of the underlying tendency so much as it inoculates you to it in specific areas of experience/expertise. Plenty of experts in their own field will look at a screw-up in another field they're not familiar with and exclaim "just do/don't do x, y,or z." That's why it's such an insidious tendency, insight really only let's you see how complicated certain things are while leaving the shroud of your own ignorance around everything else.

Think of a clerk having trouble with the register when you're in a hurry to get home. You're likely to think to yourself "come on! It's your one job and it's not that hard. But if you're made to stop and think about it you realize there's a whole litany of functions to remember for the different scenarios that come up, an encyclopedia of produce numbers to remember, company policies to be observed,and all sorts of smaller jobs to be done.

This isn't to say that people willing to hurt others for an easy solution to their problems have an excuse. This is just to say that we would do well to remember that everyone is susceptible to the urge to oversimplify.

Edit: spelling

You raise a good point. The bias towards action, real or perceived, and the catharsis of self-righteous anger are both strong motivators at work in the political realm. We'd all do well to guard ourselves against those wishing to exploit them.