The 1980s are over. This is not the time or the place for dignity as you describe it. We can no longer afford that luxury.
This is closer to the Civil War. As Lincoln once said of a certain boozy, uncouth, nasty general: “I can’t spare this man; he fights.”
Are you going to lose with what you perceive as dignity or fight and win however you can?
Being petty is not the same as fighting. And if Trump is at war with Megyn Kelly, he’s focused on the wrong enemy.