I think some people seek refuge in anger to protect them from self-doubt. Lacking self-doubt (self-confidence) can actually help a person think clearly, accurately, and without hesitation, so in that way anger can promote thinking.
Other times, deep thinking and reflection can inspire values and judgments. Reflection on politics, society, and suffering, for example, can cause a person to value peace and cooperation and become irritated with obstacles to those values -- greed, bureaucracy, people sheltering themselves. That irritation can turn into action, healthy "anger," or unhealthy anger. I'd define healthy anger and acting angry for someone's benefit because of the way anger can motivate people who aren't amenable to discussion. It's not really anger.
Sometimes people avoid the truth because they're afraid of getting unhealthily angry, like avoiding the way a spouse disrespect you because you don't want to start a fight. That can be a problem, but being open to anger isn't the only solution. Instead, you can resolve to feel angry but calculate your response so you don't inject more drama and chaos into a situation.