Thanks for this deep dive into anger, Rob.
It's also worth pointing out that one of the downsides of venting anger is that it is one of the most potent triggers for eliciting anger in others - because they feel it is unfair that they are being targeted for abuse. So expressing anger often results in a cycle of escalating anger.
As you point out, it is the skillful direction of anger that is important. Women wouldn't be voting, and Americans would still own slaves if enough people hadn't channeled their anger to overturn those injustices.