Humm, so I've got about 10 different parts with different opinions here...
I am pulled to say, there is no trauma top trumps here. That adults are not exempt from responsibility because of their own trauma, especially when children are concerned.
And then, I equally recognise that message within me all too well. Why can't I just be understanding/ compassionate/ accepting/ forgiving. Both of my birth parents had horrendous abuse histories that I was told about the from being very young. Conditioned maybe, by heck it worked, no one could ever have anything wrong, be ill, struggle etc because they had had it worse... The threshold for good parenting was as long as social services didn't take you away, you were a good parent. Therefore shut your mouth, don't talk to any of the 'nosey do gooders' and job done, you are an A* parent.
It messed me up for 30 years and it's still a message I struggle with loud and clear. So logically my brain doesn't believe it's ok, but emotional, yeah, I have a lifetime of believing that statement (which has just messed me up more...)