Saying it's all good as long as it's confined to the field of play can be dangerous.

Saying "pass was a little off target, but close enough that [insert WR] got his hands on it. That's a catch he absolutely has to make. Disappointing to see him drop so many of those" isn't an attack and is a reasonable critique.

Spewing "man, [insert LB] just flat out sucks at his job. He doesn't have the speed to play and he never will. It's even ok to be slow as molasses as long as you've got great instincts, but he's hot garbage there too. All the wrong angles. By this point it's clear that whenever he's in the field, he's a gaping black hole of suckiness that everyone else has to cover for and a guarantee that our defense will get gashed. What a waste of a scholarship" is still only critiquing on-field performance but definitely moves into attack territory.