It's not so much about punishment as it is about keeping people safe. If you can't behave in a safe manner in the air, you shouldn't be there regardless of your mental health.
That is why I requested being put on the list. I encourage others to do the same. Let Delta stew in it.
> So, I cannot fly because you, without any other knowledge, are afraid of me.
I do have knowledge. You were given an opportunity before, and knowing the risks to yourself and co-passengers, misbehaved anyway. Take the train.