Telling someone off can be a right response given the right prelude. It can actually be quite beautiful. Like punching back.
Showing anger is believed by some to be inherently violent. Others make room for it depending on the situation. However, it can be violent to demand people repress their emotions to suit your comfort or that they not defend themselves when it inconveniences you.
Inadequate responses often lack scale. A response being out of proportion to what triggered it is not necessarily in denial of what happened it, but the usage of scales might be way off.
Even when the situation did not "demand" it, showing anger is okay. Anger is just an emotion, but who decides how it should be expressed? Some scenes decide to right out banish it. Others limit it. Because it serves a purpose.
Instead of focusing on whether it is proportional, we can figure out what triggered it and what can be done about it instead of ignoring it or shoving it under the rug. Showing anger can be disruptive and we can make room for that and benefit from it.
Even if such an expression is retrospectively out of proportion, opportunities might arise. Misunderstandings may be cleared out and the usage of scales, because they were tested may be improved. Embrace disruption, moving on is actually easier if we collectively make room for big emotions.