@verius It definitely comes from a place of insecurity. I'm willing to let a lot of "transgressions" go, even sometimes large ones, because I realize that random people on the internet that disagree with me or antagonize me ultimately have exactly as much power as I give to them, and if I ignore them, that power is greatly diminished (though it doesn't go away - no one is an island after all).
But those whom are not so mature and secure in themselves see even these small things as an impediment or challenge to themselves and respond accordingly, to say nothing of people whom base their identity solely on a single trait or thing.